tinycc/tcc.c

/*
 *  TCC - Tiny C Compiler
 * 
 *  Copyright (c) 2001, 2002 Fabrice Bellard
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <math.h>
#include <unistd.h>
#include <signal.h>
#include <unistd.h>
#include <fcntl.h>
#ifndef WIN32
#include <sys/ucontext.h>
#endif
#include "elf.h"
#include "stab.h"
#ifndef CONFIG_TCC_STATIC
#include <dlfcn.h>
#endif

#include "libtcc.h"

//#define DEBUG
/* preprocessor debug */
//#define PP_DEBUG

//#define MEM_DEBUG

/* target selection */
//#define TCC_TARGET_I386   /* i386 code generator */
//#define TCC_TARGET_IL     /* .NET CLI generator */

/* default target is I386 */
#if !defined(TCC_TARGET_I386) && !defined(TCC_TARGET_IL)
#define TCC_TARGET_I386
#endif

#if !defined(WIN32) && !defined(TCC_UCLIBC) && !defined(TCC_TARGET_IL)
#define CONFIG_TCC_BCHECK /* enable bound checking code */
#endif

#ifndef CONFIG_TCC_PREFIX
#define CONFIG_TCC_PREFIX "/usr/local"
#endif

/* path to find crt1.o, crti.o and crtn.o. Only needed when generating
   executables or dlls */
#define CONFIG_TCC_CRT_PREFIX "/usr/lib"

#define INCLUDE_STACK_SIZE  32
#define IFDEF_STACK_SIZE    64
#define VSTACK_SIZE         64
#define STRING_MAX_SIZE     1024

#define TOK_HASH_SIZE       2048 /* must be a power of two */
#define TOK_ALLOC_INCR      512  /* must be a power of two */
#define SYM_HASH_SIZE       1031

/* token symbol management */
typedef struct TokenSym {
    struct TokenSym *hash_next;
    int tok; /* token number */
    int len;
    char str[1];
} TokenSym;

typedef struct CString {
    int size; /* size in bytes */
    void *data; /* either 'char *' or 'int *' */
    int size_allocated;
    void *data_allocated; /* if non NULL, data has been malloced */
} CString;

/* constant value */
typedef union CValue {
    long double ld;
    double d;
    float f;
    int i;
    unsigned int ui;
    unsigned int ul; /* address (should be unsigned long on 64 bit cpu) */
    long long ll;
    unsigned long long ull;
    struct CString *cstr;
    void *ptr;
    int tab[1];
} CValue;

/* value on stack */
typedef struct SValue {
    int t;      /* type */
    unsigned short r;      /* register + flags */
    unsigned short r2;     /* second register, used for 'long long'
                              type. If not used, set to VT_CONST */
    CValue c;              /* constant, if VT_CONST */
    struct Sym *sym;       /* symbol, if (VT_SYM | VT_CONST) */
} SValue;

/* symbol management */
typedef struct Sym {
    int v;    /* symbol token */
    int t;    /* associated type */
    int r;    /* associated register */
    int c;    /* associated number */
    struct Sym *next; /* next related symbol */
    struct Sym *prev; /* prev symbol in stack */
    struct Sym *hash_next; /* next symbol in hash table */
} Sym;

typedef struct SymStack {
  struct Sym *top;
  struct Sym *hash[SYM_HASH_SIZE];
} SymStack;

/* section definition */
/* XXX: use directly ELF structure for parameters ? */
/* special flag to indicate that the section should not be linked to
   the other ones */
#define SHF_PRIVATE 0x80000000

typedef struct Section {
    unsigned long data_offset; /* current data offset */
    unsigned char *data;       /* section data */
    unsigned long data_allocated; /* used for realloc() handling */
    int sh_name;             /* elf section name (only used during output) */
    int sh_num;              /* elf section number */
    int sh_type;             /* elf section type */
    int sh_flags;            /* elf section flags */
    int sh_info;             /* elf section info */
    int sh_addralign;        /* elf section alignment */
    int sh_entsize;          /* elf entry size */
    unsigned long sh_size;   /* section size (only used during output) */
    unsigned long sh_addr;      /* address at which the section is relocated */
    unsigned long sh_offset;      /* address at which the section is relocated */
    int nb_hashed_syms;      /* used to resize the hash table */
    struct Section *link;    /* link to another section */
    struct Section *reloc;   /* corresponding section for relocation, if any */
    struct Section *hash;     /* hash table for symbols */
    struct Section *next;
    char name[64];           /* section name */
} Section;

typedef struct DLLReference {
    int level;
    char name[1];
} DLLReference;

/* GNUC attribute definition */
typedef struct AttributeDef {
    int aligned;
    Section *section;
    unsigned char func_call; /* FUNC_CDECL or FUNC_STDCALL */
} AttributeDef;

#define SYM_STRUCT     0x40000000 /* struct/union/enum symbol space */
#define SYM_FIELD      0x20000000 /* struct/union field symbol space */
#define SYM_FIRST_ANOM (1 << (31 - VT_STRUCT_SHIFT)) /* first anonymous sym */

/* stored in 'Sym.c' field */
#define FUNC_NEW       1 /* ansi function prototype */
#define FUNC_OLD       2 /* old function prototype */
#define FUNC_ELLIPSIS  3 /* ansi function prototype with ... */

/* stored in 'Sym.r' field */
#define FUNC_CDECL     0 /* standard c call */
#define FUNC_STDCALL   1 /* pascal c call */

/* field 'Sym.t' for macros */
#define MACRO_OBJ      0 /* object like macro */
#define MACRO_FUNC     1 /* function like macro */

/* field 'Sym.t' for labels */
#define LABEL_FORWARD  1 /* label is forward defined */

/* type_decl() types */
#define TYPE_ABSTRACT  1 /* type without variable */
#define TYPE_DIRECT    2 /* type with variable */

#define IO_BUF_SIZE 8192

typedef struct BufferedFile {
    unsigned char *buf_ptr;
    unsigned char *buf_end;
    int fd;
    int line_num;    /* current line number - here to simply code */
    char filename[1024];    /* current filename - here to simplify code */
    unsigned char buffer[IO_BUF_SIZE + 1]; /* extra size for CH_EOB char */
} BufferedFile;

#define CH_EOB   0       /* end of buffer or '\0' char in file */
#define CH_EOF   (-1)   /* end of file */

/* parsing state (used to save parser state to reparse part of the
   source several times) */
typedef struct ParseState {
    int *macro_ptr;
    int line_num;
    int tok;
    CValue tokc;
} ParseState;

/* used to record tokens */
typedef struct TokenString {
    int *str;
    int len;
    int last_line_num;
} TokenString;

/* parser */
struct BufferedFile *file;
int ch, ch1, tok, tok1;
CValue tokc, tok1c;
CString tokcstr; /* current parsed string, if any */
int return_linefeed; /* if true, line feed is returned as a token */

/* sections */
Section **sections;
int nb_sections; /* number of sections, including first dummy section */
Section *text_section, *data_section, *bss_section; /* predefined sections */
Section *cur_text_section; /* current section where function code is
                              generated */
/* bound check related sections */
Section *bounds_section; /* contains global data bound description */
Section *lbounds_section; /* contains local data bound description */
/* symbol sections */
Section *symtab_section, *strtab_section;
/* temporary dynamic symbol sections (for dll loading) */
Section *dynsymtab_section;
/* exported dynamic symbol section */
Section *dynsym;
/* got handling */
Section *got;
unsigned long *got_offsets;
int nb_got_offsets;
int nb_plt_entries;
/* give the correspondance from symtab indexes to dynsym indexes */
int *symtab_to_dynsym;

/* array of all loaded dlls (including those referenced by loaded
   dlls) */
DLLReference **loaded_dlls;
int nb_loaded_dlls;

/* debug sections */
Section *stab_section, *stabstr_section;

char **library_paths;
int nb_library_paths;

/* loc : local variable index
   ind : output code index
   rsym: return symbol
   anon_sym: anonymous symbol index
*/
int rsym, anon_sym,
    prog, ind, loc, const_wanted;
int global_expr; /* true if compound literals must be allocated
                    globally (used during initializers parsing */
int func_vt, func_vc; /* current function return type (used by
                         return instruction) */
int last_line_num, last_ind, func_ind; /* debug last line number and pc */
int tok_ident;
TokenSym **table_ident;
TokenSym *hash_ident[TOK_HASH_SIZE];
char token_buf[STRING_MAX_SIZE + 1];
char *funcname;
SymStack define_stack, global_stack, local_stack, label_stack;

SValue vstack[VSTACK_SIZE], *vtop;
int *macro_ptr, *macro_ptr_allocated;
BufferedFile *include_stack[INCLUDE_STACK_SIZE], **include_stack_ptr;
int ifdef_stack[IFDEF_STACK_SIZE], *ifdef_stack_ptr;
char **include_paths;
int nb_include_paths;
char **sysinclude_paths;
int nb_sysinclude_paths;
int char_pointer_type;
int func_old_type;

/* compile with debug symbol (and use them if error during execution) */
int do_debug = 0;

/* compile with built-in memory and bounds checker */
int do_bounds_check = 0;

/* display benchmark infos */
int do_bench = 0;
int total_lines;
int total_bytes;

/* use GNU C extensions */
int gnu_ext = 1;

/* use Tiny C extensions */
int tcc_ext = 1;

/* if true, static linking is performed */
int static_link = 0;

/* give the path of the tcc libraries */
static const char *tcc_lib_path = CONFIG_TCC_PREFIX "/lib/tcc";

struct TCCState {
    int output_type;
};

/* The current value can be: */
#define VT_VALMASK   0x00ff
#define VT_CONST     0x00f0  /* constant in vc 
                              (must be first non register value) */
#define VT_LLOCAL    0x00f1  /* lvalue, offset on stack */
#define VT_LOCAL     0x00f2  /* offset on stack */
#define VT_CMP       0x00f3  /* the value is stored in processor flags (in vc) */
#define VT_JMP       0x00f4  /* value is the consequence of jmp true (even) */
#define VT_JMPI      0x00f5  /* value is the consequence of jmp false (odd) */
#define VT_LVAL      0x0100  /* var is an lvalue */
#define VT_SYM       0x0200  /* a symbol value is added */
#define VT_MUSTCAST  0x0400  /* value must be casted to be correct (used for
                                char/short stored in integer registers) */
#define VT_MUSTBOUND 0x0800  /* bound checking must be done before
                                dereferencing value */
#define VT_BOUNDED   0x8000  /* value is bounded. The address of the
                                bounding function call point is in vc */
#define VT_LVAL_BYTE     0x1000  /* lvalue is a byte */
#define VT_LVAL_SHORT    0x2000  /* lvalue is a short */
#define VT_LVAL_UNSIGNED 0x4000  /* lvalue is unsigned */
#define VT_LVAL_TYPE     (VT_LVAL_BYTE | VT_LVAL_SHORT | VT_LVAL_UNSIGNED)

/* types */
#define VT_STRUCT_SHIFT 12   /* structure/enum name shift (20 bits left) */

#define VT_INT        0  /* integer type */
#define VT_BYTE       1  /* signed byte type */
#define VT_SHORT      2  /* short type */
#define VT_VOID       3  /* void type */
#define VT_PTR        4  /* pointer */
#define VT_ENUM       5  /* enum definition */
#define VT_FUNC       6  /* function type */
#define VT_STRUCT     7  /* struct/union definition */
#define VT_FLOAT      8  /* IEEE float */
#define VT_DOUBLE     9  /* IEEE double */
#define VT_LDOUBLE   10  /* IEEE long double */
#define VT_BOOL      11  /* ISOC99 boolean type */
#define VT_LLONG     12  /* 64 bit integer */
#define VT_LONG      13  /* long integer (NEVER USED as type, only
                            during parsing) */
#define VT_BTYPE      0x000f /* mask for basic type */
#define VT_UNSIGNED   0x0010  /* unsigned type */
#define VT_ARRAY      0x0020  /* array type (also has VT_PTR) */
#define VT_BITFIELD   0x0040  /* bitfield modifier */

/* storage */
#define VT_EXTERN  0x00000080  /* extern definition */
#define VT_STATIC  0x00000100  /* static variable */
#define VT_TYPEDEF 0x00000200  /* typedef definition */

/* type mask (except storage) */
#define VT_TYPE    (~(VT_EXTERN | VT_STATIC | VT_TYPEDEF))

/* token values */

/* warning: the following compare tokens depend on i386 asm code */
#define TOK_ULT 0x92
#define TOK_UGE 0x93
#define TOK_EQ  0x94
#define TOK_NE  0x95
#define TOK_ULE 0x96
#define TOK_UGT 0x97
#define TOK_LT  0x9c
#define TOK_GE  0x9d
#define TOK_LE  0x9e
#define TOK_GT  0x9f

#define TOK_LAND  0xa0
#define TOK_LOR   0xa1

#define TOK_DEC   0xa2
#define TOK_MID   0xa3 /* inc/dec, to void constant */
#define TOK_INC   0xa4
#define TOK_UDIV  0xb0 /* unsigned division */
#define TOK_UMOD  0xb1 /* unsigned modulo */
#define TOK_PDIV  0xb2 /* fast division with undefined rounding for pointers */
#define TOK_CINT   0xb3 /* number in tokc */
#define TOK_CCHAR 0xb4 /* char constant in tokc */
#define TOK_STR   0xb5 /* pointer to string in tokc */
#define TOK_TWOSHARPS 0xb6 /* ## preprocessing token */
#define TOK_LCHAR    0xb7
#define TOK_LSTR     0xb8
#define TOK_CFLOAT   0xb9 /* float constant */
#define TOK_LINENUM  0xba /* line number info */
#define TOK_CDOUBLE  0xc0 /* double constant */
#define TOK_CLDOUBLE 0xc1 /* long double constant */
#define TOK_UMULL    0xc2 /* unsigned 32x32 -> 64 mul */
#define TOK_ADDC1    0xc3 /* add with carry generation */
#define TOK_ADDC2    0xc4 /* add with carry use */
#define TOK_SUBC1    0xc5 /* add with carry generation */
#define TOK_SUBC2    0xc6 /* add with carry use */
#define TOK_CUINT    0xc8 /* unsigned int constant */
#define TOK_CLLONG   0xc9 /* long long constant */
#define TOK_CULLONG  0xca /* unsigned long long constant */
#define TOK_ARROW    0xcb
#define TOK_DOTS     0xcc /* three dots */
#define TOK_SHR      0xcd /* unsigned shift right */

#define TOK_SHL   0x01 /* shift left */
#define TOK_SAR   0x02 /* signed shift right */
  
/* assignement operators : normal operator or 0x80 */
#define TOK_A_MOD 0xa5
#define TOK_A_AND 0xa6
#define TOK_A_MUL 0xaa
#define TOK_A_ADD 0xab
#define TOK_A_SUB 0xad
#define TOK_A_DIV 0xaf
#define TOK_A_XOR 0xde
#define TOK_A_OR  0xfc
#define TOK_A_SHL 0x81
#define TOK_A_SAR 0x82

/* WARNING: the content of this string encodes token numbers */
static char tok_two_chars[] = "<=\236>=\235!=\225&&\240||\241++\244--\242==\224<<\1>>\2+=\253-=\255*=\252/=\257%=\245&=\246^=\336|=\374->\313..\250##\266";

#define TOK_EOF       (-1)  /* end of file */
#define TOK_LINEFEED  10    /* line feed */

/* all identificators and strings have token above that */
#define TOK_IDENT 256

enum {
    TOK_INT = TOK_IDENT,
    TOK_VOID,
    TOK_CHAR,
    TOK_IF,
    TOK_ELSE,
    TOK_WHILE,
    TOK_BREAK,
    TOK_RETURN,
    TOK_FOR,
    TOK_EXTERN,
    TOK_STATIC,
    TOK_UNSIGNED,
    TOK_GOTO,
    TOK_DO,
    TOK_CONTINUE,
    TOK_SWITCH,
    TOK_CASE,

    /* ignored types Must have contiguous values */
    TOK_CONST,
    TOK_VOLATILE,
    TOK_LONG,
    TOK_REGISTER,
    TOK_SIGNED,
    TOK___SIGNED__, /* gcc keyword */
    TOK_AUTO,
    TOK_INLINE,
    TOK___INLINE__, /* gcc keyword */
    TOK_RESTRICT,

    /* unsupported type */
    TOK_FLOAT,
    TOK_DOUBLE,
    TOK_BOOL,

    TOK_SHORT,
    TOK_STRUCT,
    TOK_UNION,
    TOK_TYPEDEF,
    TOK_DEFAULT,
    TOK_ENUM,
    TOK_SIZEOF,
    TOK___ATTRIBUTE__,
    
    /* preprocessor only */
    TOK_UIDENT, /* first "user" ident (not keyword) */
    TOK_DEFINE = TOK_UIDENT,
    TOK_INCLUDE,
    TOK_IFDEF,
    TOK_IFNDEF,
    TOK_ELIF,
    TOK_ENDIF,
    TOK_DEFINED,
    TOK_UNDEF,
    TOK_ERROR,
    TOK_LINE,

#define DEF(id, str) id,
#include "tcctok.h"
#undef DEF
};

char *tcc_keywords = 
"int\0void\0char\0if\0else\0while\0break\0return\0for\0extern\0static\0"
"unsigned\0goto\0do\0continue\0switch\0case\0const\0volatile\0long\0"
"register\0signed\0__signed__\0auto\0inline\0__inline__\0restrict\0"
"float\0double\0_Bool\0short\0struct\0union\0typedef\0default\0enum\0"
"sizeof\0__attribute__\0"
/* the following are not keywords. They are included to ease parsing */
"define\0include\0ifdef\0ifndef\0elif\0endif\0"
"defined\0undef\0error\0line\0"
/* builtin functions */
#define DEF(id, str) str "\0"
#include "tcctok.h"
#undef DEF
;

#ifdef WIN32
#define snprintf _snprintf
#endif

#if defined(WIN32) || defined(TCC_UCLIBC)
/* currently incorrect */
long double strtold(const char *nptr, char **endptr)
{
    return (long double)strtod(nptr, endptr);
}
float strtof(const char *nptr, char **endptr)
{
    return (float)strtod(nptr, endptr);
}
#else
/* XXX: need to define this to use them in non ISOC99 context */
extern float strtof (const char *__nptr, char **__endptr);
extern long double strtold (const char *__nptr, char **__endptr);
#endif

static char *pstrcpy(char *buf, int buf_size, const char *s);
static char *pstrcat(char *buf, int buf_size, const char *s);

void sum(int l);
void next(void);
void next_nomacro(void);
static int expr_const(void);
void expr_eq(void);
void gexpr(void);
void decl(int l);
static void decl_initializer(int t, Section *sec, unsigned long c, 
                             int first, int size_only);
static void decl_initializer_alloc(int t, AttributeDef *ad, int r, 
                                   int has_init, int v, int scope);
int gv(int rc);
void gv2(int rc1, int rc2);
void move_reg(int r, int s);
void save_regs(int n);
void save_reg(int r);
void vpop(void);
void vswap(void);
void vdup(void);
int get_reg(int rc);

void macro_subst(TokenString *tok_str, 
                 Sym **nested_list, int *macro_str);
int save_reg_forced(int r);
void gen_op(int op);
void force_charshort_cast(int t);
void gen_cast(int t);
void vstore(void);
Sym *sym_find(int v);
Sym *sym_push(int v, int t, int r, int c);

/* type handling */
int type_size(int t, int *a);
int pointed_type(int t);
int pointed_size(int t);
static int lvalue_type(int t);
int is_compatible_types(int t1, int t2);
int parse_btype(int *type_ptr, AttributeDef *ad);
int type_decl(AttributeDef *ad, int *v, int t, int td);

void error(const char *fmt, ...);
void rt_error(unsigned long pc, const char *fmt, ...);
void vpushi(int v);
void vset(int t, int r, int v);
void type_to_str(char *buf, int buf_size, 
                 int t, const char *varstr);
char *get_tok_str(int v, CValue *cv);
static Sym *get_sym_ref(int t, Section *sec, 
                        unsigned long offset, unsigned long size);
static Sym *external_global_sym(int v, int u, int r);

/* section generation */
static void section_realloc(Section *sec, unsigned long new_size);
static void *section_ptr_add(Section *sec, unsigned long size);
static void put_extern_sym(Sym *sym, Section *section, 
                           unsigned long value, unsigned long size);
static void greloc(Section *s, Sym *sym, unsigned long addr, int type);
static int put_elf_str(Section *s, const char *sym);
static int put_elf_sym(Section *s, 
                       unsigned long value, unsigned long size,
                       int info, int other, int shndx, const char *name);
static int add_elf_sym(Section *s, unsigned long value, unsigned long size,
                       int info, int sh_num, const char *name);
static void put_elf_reloc(Section *symtab, Section *s, unsigned long offset,
                          int type, int symbol);
static void put_stabs(const char *str, int type, int other, int desc, 
                      unsigned long value);
static void put_stabs_r(const char *str, int type, int other, int desc, 
                        unsigned long value, Section *sec, int sym_index);
static void put_stabn(int type, int other, int desc, int value);
static void put_stabd(int type, int other, int desc);
static int tcc_add_dll(TCCState *s, const char *filename, int flags);

#define AFF_PRINT_ERROR     0x0001 /* print error if file not found */
#define AFF_REFERENCED_DLL  0x0002 /* load a referenced dll from another dll */
static int tcc_add_file_internal(TCCState *s, const char *filename, int flags);

/* true if float/double/long double type */
static inline int is_float(int t)
{
    int bt;
    bt = t & VT_BTYPE;
    return bt == VT_LDOUBLE || bt == VT_DOUBLE || bt == VT_FLOAT;
}

#ifdef TCC_TARGET_I386
#include "i386-gen.c"
#endif
#ifdef TCC_TARGET_IL
#include "il-gen.c"
#endif

#ifdef CONFIG_TCC_STATIC

#define RTLD_LAZY       0x001
#define RTLD_NOW        0x002
#define RTLD_GLOBAL     0x100

/* dummy function for profiling */
void *dlopen(const char *filename, int flag)
{
    return NULL;
}

const char *dlerror(void)
{
    return "error";
}

typedef struct TCCSyms {
    char *str;
    void *ptr;
} TCCSyms;

#define TCCSYM(a) { #a, &a, },

/* add the symbol you want here if no dynamic linking is done */
static TCCSyms tcc_syms[] = {
    TCCSYM(printf)
    TCCSYM(fprintf)
    TCCSYM(fopen)
    TCCSYM(fclose)
    { NULL, NULL },
};

void *dlsym(void *handle, const char *symbol)
{
    TCCSyms *p;
    p = tcc_syms;
    while (p->str != NULL) {
        if (!strcmp(p->str, symbol))
            return p->ptr;
        p++;
    }
    return NULL;
}

#endif

/********************************************************/

/* we use our own 'finite' function to avoid potential problems with
   non standard math libs */
/* XXX: endianness dependant */
int ieee_finite(double d)
{
    int *p = (int *)&d;
    return ((unsigned)((p[1] | 0x800fffff) + 1)) >> 31;
}

/* copy a string and truncate it. */
static char *pstrcpy(char *buf, int buf_size, const char *s)
{
    char *q, *q_end;
    int c;

    if (buf_size > 0) {
        q = buf;
        q_end = buf + buf_size - 1;
        while (q < q_end) {
            c = *s++;
            if (c == '\0')
                break;
            *q++ = c;
        }
        *q = '\0';
    }
    return buf;
}

/* strcat and truncate. */
static char *pstrcat(char *buf, int buf_size, const char *s)
{
    int len;
    len = strlen(buf);
    if (len < buf_size) 
        pstrcpy(buf + len, buf_size - len, s);
    return buf;
}

/* memory management */
#ifdef MEM_DEBUG
int mem_cur_size;
int mem_max_size;
#endif

static inline void tcc_free(void *ptr)
{
#ifdef MEM_DEBUG
    mem_cur_size -= malloc_usable_size(ptr);
#endif
    free(ptr);
}

static void *tcc_malloc(unsigned long size)
{
    void *ptr;
    ptr = malloc(size);
    if (!ptr)
        error("memory full");
#ifdef MEM_DEBUG
    mem_cur_size += malloc_usable_size(ptr);
    if (mem_cur_size > mem_max_size)
        mem_max_size = mem_cur_size;
#endif
    return ptr;
}

static void *tcc_mallocz(unsigned long size)
{
    void *ptr;
    ptr = tcc_malloc(size);
    memset(ptr, 0, size);
    return ptr;
}

static inline void *tcc_realloc(void *ptr, unsigned long size)
{
    void *ptr1;
#ifdef MEM_DEBUG
    mem_cur_size -= malloc_usable_size(ptr);
#endif
    ptr1 = realloc(ptr, size);
#ifdef MEM_DEBUG
    /* NOTE: count not correct if alloc error, but not critical */
    mem_cur_size += malloc_usable_size(ptr1);
    if (mem_cur_size > mem_max_size)
        mem_max_size = mem_cur_size;
#endif
    return ptr1;
}

static char *tcc_strdup(const char *str)
{
    char *ptr;
    ptr = tcc_malloc(strlen(str) + 1);
    strcpy(ptr, str);
    return ptr;
}

#define free(p) use_tcc_free(p)
#define malloc(s) use_tcc_malloc(s)
#define realloc(p, s) use_tcc_realloc(p, s)

static void dynarray_add(void ***ptab, int *nb_ptr, void *data)
{
    int nb, nb_alloc;
    void **pp;
    
    nb = *nb_ptr;
    pp = *ptab;
    /* every power of two we double array size */
    if ((nb & (nb - 1)) == 0) {
        if (!nb)
            nb_alloc = 1;
        else
            nb_alloc = nb * 2;
        pp = tcc_realloc(pp, nb_alloc * sizeof(void *));
        if (!pp)
            error("memory full");
        *ptab = pp;
    }
    pp[nb++] = data;
    *nb_ptr = nb;
}

Section *new_section(const char *name, int sh_type, int sh_flags)
{
    Section *sec;

    sec = tcc_mallocz(sizeof(Section));
    pstrcpy(sec->name, sizeof(sec->name), name);
    sec->sh_type = sh_type;
    sec->sh_flags = sh_flags;
    switch(sh_type) {
    case SHT_HASH:
    case SHT_REL:
    case SHT_DYNSYM:
    case SHT_SYMTAB:
    case SHT_DYNAMIC:
        sec->sh_addralign = 4;
        break;
    case SHT_STRTAB:
        sec->sh_addralign = 1;
        break;
    default:
        sec->sh_addralign = 32; /* default conservative alignment */
        break;
    }

    /* only add section if not private */
    if (!(sh_flags & SHF_PRIVATE)) {
        sec->sh_num = nb_sections;
        dynarray_add((void ***)&sections, &nb_sections, sec);
    }
    return sec;
}

/* realloc section and set its content to zero */
static void section_realloc(Section *sec, unsigned long new_size)
{
    unsigned long size;
    unsigned char *data;
    
    size = sec->data_allocated;
    if (size == 0)
        size = 1;
    while (size < new_size)
        size = size * 2;
    data = tcc_realloc(sec->data, size);
    if (!data)
        error("memory full");
    memset(data + sec->data_allocated, 0, size - sec->data_allocated);
    sec->data = data;
    sec->data_allocated = size;
}

/* reserve at least 'size' bytes in section 'sec' from
   sec->data_offset. */
static void *section_ptr_add(Section *sec, unsigned long size)
{
    unsigned long offset, offset1;

    offset = sec->data_offset;
    offset1 = offset + size;
    if (offset1 > sec->data_allocated)
        section_realloc(sec, offset1);
    sec->data_offset = offset1;
    return sec->data + offset;
}

/* return a reference to a section, and create it if it does not
   exists */
Section *find_section(const char *name)
{
    Section *sec;
    int i;
    for(i = 1; i < nb_sections; i++) {
        sec = sections[i];
        if (!strcmp(name, sec->name)) 
            return sec;
    }
    /* sections are created as PROGBITS */
    return new_section(name, SHT_PROGBITS, SHF_ALLOC);
}

/* update sym->c so that it points to an external symbol in section
   'section' with value 'value' */
static void put_extern_sym(Sym *sym, Section *section, 
                           unsigned long value, unsigned long size)
{
    int sym_type, sym_bind, sh_num, info;
    Elf32_Sym *esym;
    const char *name;
    char buf[32];

    if (section)
        sh_num = section->sh_num;
    else
        sh_num = SHN_UNDEF;
    if (!sym->c) {
        if ((sym->t & VT_BTYPE) == VT_FUNC)
            sym_type = STT_FUNC;
        else
            sym_type = STT_OBJECT;
        if (sym->t & VT_STATIC)
            sym_bind = STB_LOCAL;
        else
            sym_bind = STB_GLOBAL;
        
        name = get_tok_str(sym->v, NULL);
#ifdef CONFIG_TCC_BCHECK
        if (do_bounds_check) {
            /* if bound checking is activated, we change some function
               names by adding the "__bound" prefix */
            switch(sym->v) {
            case TOK_malloc: 
            case TOK_free: 
            case TOK_realloc: 
            case TOK_memalign: 
            case TOK_calloc: 
            case TOK_memcpy: 
            case TOK_memmove:
            case TOK_memset:
            case TOK_strlen:
            case TOK_strcpy:
                strcpy(buf, "__bound_");
                strcat(buf, name);
                name = buf;
                break;
            }
        }
#endif
        info = ELF32_ST_INFO(sym_bind, sym_type);
        sym->c = add_elf_sym(symtab_section, value, size, info, sh_num, name);
    } else {
        esym = &((Elf32_Sym *)symtab_section->data)[sym->c];
        esym->st_value = value;
        esym->st_size = size;
        esym->st_shndx = sh_num;
    }
}

/* add a new relocation entry to symbol 'sym' in section 's' */
static void greloc(Section *s, Sym *sym, unsigned long offset, int type)
{
    if (!sym->c) 
        put_extern_sym(sym, NULL, 0, 0);
    /* now we can add ELF relocation info */
    put_elf_reloc(symtab_section, s, offset, type, sym->c);
}

static inline int isid(int c)
{
    return (c >= 'a' && c <= 'z') ||
        (c >= 'A' && c <= 'Z') ||
        c == '_';
}

static inline int isnum(int c)
{
    return c >= '0' && c <= '9';
}

static inline int toup(int c)
{
    if (ch >= 'a' && ch <= 'z')
        return ch - 'a' + 'A';
    else
        return ch;
}

void printline(void)
{
    BufferedFile **f;

    if (file) {
        for(f = include_stack; f < include_stack_ptr; f++)
            fprintf(stderr, "In file included from %s:%d:\n", 
                    (*f)->filename, (*f)->line_num);
        if (file->line_num > 0) {
            fprintf(stderr, "%s:%d: ", file->filename, file->line_num);
        } else {
            fprintf(stderr, "%s: ", file->filename);
        }
    } else {
        fprintf(stderr, "tcc: ");
    }
}

void error(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    printline();
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
    exit(1);
    va_end(ap);
}

void expect(const char *msg)
{
    error("%s expected", msg);
}

void warning(const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    printline();
    fprintf(stderr, "warning: ");
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
    va_end(ap);
}

void skip(int c)
{
    if (tok != c)
        error("'%c' expected", c);
    next();
}

void test_lvalue(void)
{
    if (!(vtop->r & VT_LVAL))
        expect("lvalue");
}

TokenSym *tok_alloc(const char *str, int len)
{
    TokenSym *ts, **pts, **ptable;
    int h, i;
    
    if (len <= 0)
        len = strlen(str);
    h = 1;
    for(i=0;i<len;i++)
        h = (h * 263 +  ((unsigned char *)str)[i]) & (TOK_HASH_SIZE - 1);

    pts = &hash_ident[h];
    while (1) {
        ts = *pts;
        if (!ts)
            break;
        if (ts->len == len && !memcmp(ts->str, str, len))
            return ts;
        pts = &(ts->hash_next);
    }

    if (tok_ident >= SYM_FIRST_ANOM) 
        error("memory full");

    /* expand token table if needed */
    i = tok_ident - TOK_IDENT;
    if ((i % TOK_ALLOC_INCR) == 0) {
        ptable = tcc_realloc(table_ident, (i + TOK_ALLOC_INCR) * sizeof(TokenSym *));
        if (!ptable)
            error("memory full");
        table_ident = ptable;
    }

    ts = tcc_malloc(sizeof(TokenSym) + len);
    table_ident[i] = ts;
    ts->tok = tok_ident++;
    ts->len = len;
    ts->hash_next = NULL;
    memcpy(ts->str, str, len + 1);
    *pts = ts;
    return ts;
}

/* CString handling */

static void cstr_realloc(CString *cstr, int new_size)
{
    int size;
    void *data;

    size = cstr->size_allocated;
    if (size == 0)
        size = 8; /* no need to allocate a too small first string */
    while (size < new_size)
        size = size * 2;
    data = tcc_realloc(cstr->data_allocated, size);
    if (!data)
        error("memory full");
    cstr->data_allocated = data;
    cstr->size_allocated = size;
    cstr->data = data;
}

/* add a byte */
static void cstr_ccat(CString *cstr, int ch)
{
    int size;
    size = cstr->size + 1;
    if (size > cstr->size_allocated)
        cstr_realloc(cstr, size);
    ((unsigned char *)cstr->data)[size - 1] = ch;
    cstr->size = size;
}

static void cstr_cat(CString *cstr, const char *str)
{
    int c;
    for(;;) {
        c = *str;
        if (c == '\0')
            break;
        cstr_ccat(cstr, c);
        str++;
    }
}

/* add a wide char */
static void cstr_wccat(CString *cstr, int ch)
{
    int size;
    size = cstr->size + sizeof(int);
    if (size > cstr->size_allocated)
        cstr_realloc(cstr, size);
    *(int *)(((unsigned char *)cstr->data) + size - sizeof(int)) = ch;
    cstr->size = size;
}

static void cstr_new(CString *cstr)
{
    memset(cstr, 0, sizeof(CString));
}

/* free string and reset it to NULL */
static void cstr_free(CString *cstr)
{
    tcc_free(cstr->data_allocated);
    cstr_new(cstr);
}

#define cstr_reset(cstr) cstr_free(cstr)

/* XXX: unicode ? */
static void add_char(CString *cstr, int c)
{
    if (c == '\'' || c == '\"' || c == '\\') {
        /* XXX: could be more precise if char or string */
        cstr_ccat(cstr, '\\');
    }
    if (c >= 32 && c <= 126) {
        cstr_ccat(cstr, c);
    } else {
        cstr_ccat(cstr, '\\');
        if (c == '\n') {
            cstr_ccat(cstr, 'n');
        } else {
            cstr_ccat(cstr, '0' + ((c >> 6) & 7));
            cstr_ccat(cstr, '0' + ((c >> 3) & 7));
            cstr_ccat(cstr, '0' + (c & 7));
        }
    }
}

/* XXX: buffer overflow */
/* XXX: float tokens */
char *get_tok_str(int v, CValue *cv)
{
    static char buf[STRING_MAX_SIZE + 1];
    static CString cstr_buf;
    CString *cstr;
    unsigned char *q;
    char *p;
    int i, len;

    /* NOTE: to go faster, we give a fixed buffer for small strings */
    cstr_reset(&cstr_buf);
    cstr_buf.data = buf;
    cstr_buf.size_allocated = sizeof(buf);
    p = buf;

    switch(v) {
    case TOK_CINT:
    case TOK_CUINT:
        /* XXX: not exact */
        sprintf(p, "%u", cv->ui);
        break;
    case TOK_CCHAR:
    case TOK_LCHAR:
        cstr_ccat(&cstr_buf, '\'');
        add_char(&cstr_buf, cv->i);
        cstr_ccat(&cstr_buf, '\'');
        cstr_ccat(&cstr_buf, '\0');
        break;
    case TOK_STR:
    case TOK_LSTR:
        cstr = cv->cstr;
        cstr_ccat(&cstr_buf, '\"');
        if (v == TOK_STR) {
            len = cstr->size - 1;
            for(i=0;i<len;i++)
                add_char(&cstr_buf, ((unsigned char *)cstr->data)[i]);
        } else {
            len = (cstr->size / sizeof(int)) - 1;
            for(i=0;i<len;i++)
                add_char(&cstr_buf, ((int *)cstr->data)[i]);
        }
        cstr_ccat(&cstr_buf, '\"');
        cstr_ccat(&cstr_buf, '\0');
        break;
    case TOK_LT:
        v = '<';
        goto addv;
    case TOK_GT:
        v = '>';
        goto addv;
    case TOK_A_SHL:
        return strcpy(p, "<<=");
    case TOK_A_SAR:
        return strcpy(p, ">>=");
    default:
        if (v < TOK_IDENT) {
            /* search in two bytes table */
            q = tok_two_chars;
            while (*q) {
                if (q[2] == v) {
                    *p++ = q[0];
                    *p++ = q[1];
                    *p = '\0';
                    return buf;
                }
                q += 3;
            }
        addv:
            *p++ = v;
            *p = '\0';
        } else if (v < tok_ident) {
            return table_ident[v - TOK_IDENT]->str;
        } else if (v >= SYM_FIRST_ANOM) {
            /* special name for anonymous symbol */
            sprintf(p, "L.%u", v - SYM_FIRST_ANOM);
        } else {
            /* should never happen */
            return NULL;
        }
        break;
    }
    return cstr_buf.data;
}

/* push, without hashing */
Sym *sym_push2(Sym **ps, int v, int t, int c)
{
    Sym *s;
    s = tcc_malloc(sizeof(Sym));
    s->v = v;
    s->t = t;
    s->c = c;
    s->next = NULL;
    /* add in stack */
    s->prev = *ps;
    *ps = s;
    return s;
}

/* find a symbol and return its associated structure. 's' is the top
   of the symbol stack */
Sym *sym_find2(Sym *s, int v)
{
    while (s) {
        if (s->v == v)
            return s;
        s = s->prev;
    }
    return NULL;
}

#define HASH_SYM(v) ((unsigned)(v) % SYM_HASH_SIZE)

/* find a symbol and return its associated structure. 'st' is the
   symbol stack */
Sym *sym_find1(SymStack *st, int v)
{
    Sym *s;

    s = st->hash[HASH_SYM(v)];
    while (s) {
        if (s->v == v)
            return s;
        s = s->hash_next;
    }
    return NULL;
}

Sym *sym_push1(SymStack *st, int v, int t, int c)
{
    Sym *s, **ps;
    s = sym_push2(&st->top, v, t, c);
    /* add in hash table */
    if (v) {
        ps = &st->hash[HASH_SYM(v)];
        s->hash_next = *ps;
        *ps = s;
    }
    return s;
}

/* find a symbol in the right symbol space */
Sym *sym_find(int v)
{
    Sym *s;
    s = sym_find1(&local_stack, v);
    if (!s)
        s = sym_find1(&global_stack, v);
    return s;
}

/* push a given symbol on the symbol stack */
Sym *sym_push(int v, int t, int r, int c)
{
    Sym *s;
    if (local_stack.top)
        s = sym_push1(&local_stack, v, t, c);
    else
        s = sym_push1(&global_stack, v, t, c);
    s->r = r;
    return s;
}

/* pop symbols until top reaches 'b' */
void sym_pop(SymStack *st, Sym *b)
{
    Sym *s, *ss;

    s = st->top;
    while(s != b) {
        ss = s->prev;
        /* free hash table entry, except if symbol was freed (only
           used for #undef symbols) */
        if (s->v)
            st->hash[HASH_SYM(s->v)] = s->hash_next;
        tcc_free(s);
        s = ss;
    }
    st->top = b;
}

/* undefined a hashed symbol (used for #undef). Its name is set to
   zero */
void sym_undef(SymStack *st, Sym *s)
{
    Sym **ss;
    ss = &st->hash[HASH_SYM(s->v)];
    while (*ss != NULL) {
        if (*ss == s)
            break;
        ss = &(*ss)->hash_next;
    }
    *ss = s->hash_next;
    s->v = 0;
}

/* I/O layer */

BufferedFile *tcc_open(const char *filename)
{
    int fd;
    BufferedFile *bf;

    fd = open(filename, O_RDONLY);
    if (fd < 0)
        return NULL;
    bf = tcc_malloc(sizeof(BufferedFile));
    if (!bf) {
        close(fd);
        return NULL;
    }
    bf->fd = fd;
    bf->buf_ptr = bf->buffer;
    bf->buf_end = bf->buffer;
    bf->buffer[0] = CH_EOB; /* put eob symbol */
    pstrcpy(bf->filename, sizeof(bf->filename), filename);
    bf->line_num = 1;
    //    printf("opening '%s'\n", filename);
    return bf;
}

void tcc_close(BufferedFile *bf)
{
    total_lines += bf->line_num;
    close(bf->fd);
    tcc_free(bf);
}

/* read one char. MUST call tcc_fillbuf if CH_EOB is read */
#define TCC_GETC(bf) (*(bf)->buf_ptr++)

/* fill input buffer and return next char */
int tcc_getc_slow(BufferedFile *bf)
{
    int len;
    /* only tries to read if really end of buffer */
    if (bf->buf_ptr >= bf->buf_end) {
        if (bf->fd != -1) {
            len = read(bf->fd, bf->buffer, IO_BUF_SIZE);
            if (len < 0)
                len = 0;
        } else {
            len = 0;
        }
        total_bytes += len;
        bf->buf_ptr = bf->buffer;
        bf->buf_end = bf->buffer + len;
        *bf->buf_end = CH_EOB;
    }
    if (bf->buf_ptr < bf->buf_end) {
        return *bf->buf_ptr++;
    } else {
        bf->buf_ptr = bf->buf_end;
        return CH_EOF;
    }
}

/* no need to put that inline */
void handle_eob(void)
{
    for(;;) {
        ch1 = tcc_getc_slow(file);
        if (ch1 != CH_EOF)
            return;
        
        if (include_stack_ptr == include_stack)
            return;
        /* add end of include file debug info */
        if (do_debug) {
            put_stabd(N_EINCL, 0, 0);
        }
        /* pop include stack */
        tcc_close(file);
        include_stack_ptr--;
        file = *include_stack_ptr;
    }
}

/* read next char from current input file */
static inline void inp(void)
{
    ch1 = TCC_GETC(file);
    /* end of buffer/file handling */
    if (ch1 == CH_EOB)
        handle_eob();
    if (ch1 == '\n')
        file->line_num++;
    //    printf("ch1=%c 0x%x\n", ch1, ch1);
}

/* handle '\\n' and '\\r\n' */
static void handle_stray(void)
{
    do {
        if (ch1 == '\n') {
            inp();
        } else if (ch1 == '\r') {
            inp();
            if (ch1 != '\n')
                error("invalid character after '\\'");
            inp();
        } else {
            break;
        }
        ch = ch1;
        inp();
    } while (ch == '\\');
}

/* input with '\\n' handling. Also supports '\\r\n' for horrible MSDOS
   case */
static inline void minp(void)
{
    ch = ch1;
    inp();
    if (ch == '\\') 
        handle_stray();
}


/* same as minp, but also skip comments */
static void cinp(void)
{
    int c;

    if (ch1 == '/') {
        inp();
        if (ch1 == '/') {
            /* single line C++ comments */
            inp();
            while (ch1 != '\n' && ch1 != CH_EOF)
                inp();
            ch = ' '; /* return space */
        } else if (ch1 == '*') {
            /* C comments */
            inp();
            while (ch1 != CH_EOF) {
                c = ch1;
                inp();
            if (c == '*' && ch1 == '/') {
                inp();
                ch = ' '; /* return space */
                break;
            }
            }
        } else {
            ch = '/';
        }
    } else {
        minp();
    }
}

/* space exlcuding newline */
static inline int is_space(int ch)
{
    return ch == ' ' || ch == '\t' || ch == '\v' || ch == '\f' || ch == '\r';
}

static inline void skip_spaces(void)
{
    while (is_space(ch))
        cinp();
}

/* skip block of text until #else, #elif or #endif. skip also pairs of
   #if/#endif */
void preprocess_skip(void)
{
    int a;
    a = 0;
    while (1) {
        while (ch != '\n') {
            if (ch == CH_EOF)
                expect("#endif");
            cinp();
        }
        cinp();
        skip_spaces();
        if (ch == '#') {
            cinp();
            next_nomacro();
            if (a == 0 && 
                (tok == TOK_ELSE || tok == TOK_ELIF || tok == TOK_ENDIF))
                break;
            if (tok == TOK_IF || tok == TOK_IFDEF || tok == TOK_IFNDEF)
                a++;
            else if (tok == TOK_ENDIF)
                a--;
        }
    }
}

/* ParseState handling */

/* XXX: currently, no include file info is stored. Thus, we cannot display
   accurate messages if the function or data definition spans multiple
   files */

/* save current parse state in 's' */
void save_parse_state(ParseState *s)
{
    s->line_num = file->line_num;
    s->macro_ptr = macro_ptr;
    s->tok = tok;
    s->tokc = tokc;
}

/* restore parse state from 's' */
void restore_parse_state(ParseState *s)
{
    file->line_num = s->line_num;
    macro_ptr = s->macro_ptr;
    tok = s->tok;
    tokc = s->tokc;
}

/* return the number of additionnal 'ints' necessary to store the
   token */
static inline int tok_ext_size(int t)
{
    switch(t) {
        /* 4 bytes */
    case TOK_CINT:
    case TOK_CUINT:
    case TOK_CCHAR:
    case TOK_LCHAR:
    case TOK_STR:
    case TOK_LSTR:
    case TOK_CFLOAT:
    case TOK_LINENUM:
        return 1;
    case TOK_CDOUBLE:
    case TOK_CLLONG:
    case TOK_CULLONG:
        return 2;
    case TOK_CLDOUBLE:
        return LDOUBLE_SIZE / 4;
    default:
        return 0;
    }
}

/* token string handling */

static inline void tok_str_new(TokenString *s)
{
    s->str = NULL;
    s->len = 0;
    s->last_line_num = -1;
}

static void tok_str_free(int *str)
{
    const int *p;
    CString *cstr;
    int t;

    p = str;
    for(;;) {
        t = *p++;
        if (t == 0)
            break;
        if (t == TOK_STR || t == TOK_LSTR) {
            /* XXX: use a macro to be portable on 64 bit ? */
            cstr = (CString *)(*p++);
            cstr_free(cstr);
            tcc_free(cstr);
        } else {
            p += tok_ext_size(t);
        }
    }
    tcc_free(str);
}

static void tok_str_add(TokenString *s, int t)
{
    int len, *str;

    len = s->len;
    str = s->str;
    if ((len & 63) == 0) {
        str = tcc_realloc(str, (len + 64) * sizeof(int));
        if (!str)
            return;
        s->str = str;
    }
    str[len++] = t;
    s->len = len;
}

static void tok_str_add2(TokenString *s, int t, CValue *cv)
{
    int n, i, size;
    CString *cstr, *cstr1;
    CValue cv1;

    tok_str_add(s, t);
    if (t == TOK_STR || t == TOK_LSTR) {
        /* special case: need to duplicate string */
        cstr1 = cv->cstr;
        cstr = tcc_malloc(sizeof(CString));
        size = cstr1->size;
        cstr->size = size;
        cstr->size_allocated = size;
        cstr->data_allocated = tcc_malloc(size);
        cstr->data = cstr->data_allocated;
        memcpy(cstr->data_allocated, cstr1->data_allocated, size);
        cv1.cstr = cstr;
        tok_str_add(s, cv1.tab[0]);
    } else {
        n = tok_ext_size(t);
        for(i=0;i<n;i++)
            tok_str_add(s, cv->tab[i]);
    }
}

/* add the current parse token in token string 's' */
static void tok_str_add_tok(TokenString *s)
{
    CValue cval;

    /* save line number info */
    if (file->line_num != s->last_line_num) {
        s->last_line_num = file->line_num;
        cval.i = s->last_line_num;
        tok_str_add2(s, TOK_LINENUM, &cval);
    }
    tok_str_add2(s, tok, &tokc);
}

/* get a token from an integer array and increment pointer accordingly */
static int tok_get(int **tok_str, CValue *cv)
{
    int *p, t, n, i;

    p = *tok_str;
    t = *p++;
    n = tok_ext_size(t);
    for(i=0;i<n;i++)
        cv->tab[i] = *p++;
    *tok_str = p;
    return t;
}

/* eval an expression for #if/#elif */
int expr_preprocess(void)
{
    int c, t;
    TokenString str;
    
    tok_str_new(&str);
    while (tok != TOK_LINEFEED && tok != TOK_EOF) {
        next(); /* do macro subst */
        if (tok == TOK_DEFINED) {
            next_nomacro();
            t = tok;
            if (t == '(') 
                next_nomacro();
            c = sym_find1(&define_stack, tok) != 0;
            if (t == '(')
                next_nomacro();
            tok = TOK_CINT;
            tokc.i = c;
        } else if (tok >= TOK_IDENT) {
            /* if undefined macro */
            tok = TOK_CINT;
            tokc.i = 0;
        }
        tok_str_add_tok(&str);
    }
    tok_str_add(&str, -1); /* simulate end of file */
    tok_str_add(&str, 0);
    /* now evaluate C constant expression */
    macro_ptr = str.str;
    next();
    c = expr_const();
    macro_ptr = NULL;
    tok_str_free(str.str);
    return c != 0;
}

#if defined(DEBUG) || defined(PP_DEBUG)
void tok_print(int *str)
{
    int t;
    CValue cval;

    while (1) {
        t = tok_get(&str, &cval);
        if (!t)
            break;
        printf(" %s", get_tok_str(t, &cval));
    }
    printf("\n");
}
#endif

/* parse after #define */
void parse_define(void)
{
    Sym *s, *first, **ps;
    int v, t, varg, is_vaargs;
    TokenString str;
    
    v = tok;
    /* XXX: should check if same macro (ANSI) */
    first = NULL;
    t = MACRO_OBJ;
    /* '(' must be just after macro definition for MACRO_FUNC */
    if (ch == '(') {
        next_nomacro();
        next_nomacro();
        ps = &first;
        while (tok != ')') {
            varg = tok;
            next_nomacro();
            is_vaargs = 0;
            if (varg == TOK_DOTS) {
                varg = TOK___VA_ARGS__;
                is_vaargs = 1;
            } else if (tok == TOK_DOTS && gnu_ext) {
                is_vaargs = 1;
                next_nomacro();
            }
            if (varg < TOK_IDENT)
                error("badly punctuated parameter list");
            s = sym_push1(&define_stack, varg | SYM_FIELD, is_vaargs, 0);
            *ps = s;
            ps = &s->next;
            if (tok != ',')
                break;
            next_nomacro();
        }
        t = MACRO_FUNC;
    }
    tok_str_new(&str);
    while (1) {
        skip_spaces();
        if (ch == '\n' || ch == CH_EOF)
            break;
        next_nomacro();
        tok_str_add2(&str, tok, &tokc);
    }
    tok_str_add(&str, 0);
#ifdef PP_DEBUG
    printf("define %s %d: ", get_tok_str(v, NULL), t);
    tok_print(str.str);
#endif
    s = sym_push1(&define_stack, v, t, (int)str.str);
    s->next = first;
}

void preprocess(void)
{
    int size, i, c, n;
    char buf[1024], *q, *p;
    char buf1[1024];
    BufferedFile *f;
    Sym *s;

    return_linefeed = 1; /* linefeed will be returned as a token */
    cinp();
    next_nomacro();
 redo:
    if (tok == TOK_DEFINE) {
        next_nomacro();
        parse_define();
    } else if (tok == TOK_UNDEF) {
        next_nomacro();
        s = sym_find1(&define_stack, tok);
        /* undefine symbol by putting an invalid name */
        if (s)
            sym_undef(&define_stack, s);
    } else if (tok == TOK_INCLUDE) {
        skip_spaces();
        if (ch == '<') {
            c = '>';
            goto read_name;
        } else if (ch == '\"') {
            c = ch;
        read_name:
            minp();
            q = buf;
            while (ch != c && ch != '\n' && ch != CH_EOF) {
                if ((q - buf) < sizeof(buf) - 1)
                    *q++ = ch;
                minp();
            }
            *q = '\0';
            /* eat all spaces and comments after include */
            /* XXX: slightly incorrect */
            while (ch1 != '\n' && ch1 != CH_EOF)
                inp();
        } else {
            /* computed #include : either we have only strings or
               we have anything enclosed in '<>' */
            next();
            buf[0] = '\0';
            if (tok == TOK_STR) {
                while (tok != TOK_LINEFEED) {
                    if (tok != TOK_STR) {
                    include_syntax:
                        error("'#include' expects \"FILENAME\" or <FILENAME>");
                    }
                    pstrcat(buf, sizeof(buf), (char *)tokc.cstr->data);
                    next();
                }
                c = '\"';
            } else {
                int len;
                while (tok != TOK_LINEFEED) {
                    pstrcat(buf, sizeof(buf), get_tok_str(tok, &tokc));
                    next();
                }
                len = strlen(buf);
                /* check syntax and remove '<>' */
                if (len < 2 || buf[0] != '<' || buf[len - 1] != '>')
                    goto include_syntax;
                memmove(buf, buf + 1, len - 2);
                buf[len - 2] = '\0';
                c = '>';
            }
        }

        if (include_stack_ptr >= include_stack + INCLUDE_STACK_SIZE)
            error("memory full");
        if (c == '\"') {
            /* first search in current dir if "header.h" */
            size = 0;
            p = strrchr(file->filename, '/');
            if (p) 
                size = p + 1 - file->filename;
            if (size > sizeof(buf1) - 1)
                size = sizeof(buf1) - 1;
            memcpy(buf1, file->filename, size);
            buf1[size] = '\0';
            pstrcat(buf1, sizeof(buf1), buf);
            f = tcc_open(buf1);
            if (f)
                goto found;
        }
        /* now search in all the include paths */
        n = nb_include_paths + nb_sysinclude_paths;
        for(i = 0; i < n; i++) {
            const char *path;
            if (i < nb_include_paths)
                path = include_paths[i];
            else
                path = sysinclude_paths[i - nb_include_paths];
            pstrcpy(buf1, sizeof(buf1), path);
            pstrcat(buf1, sizeof(buf1), "/");
            pstrcat(buf1, sizeof(buf1), buf);
            f = tcc_open(buf1);
            if (f)
                goto found;
        }
        error("include file '%s' not found", buf);
        f = NULL;
    found:
        /* push current file in stack */
        /* XXX: fix current line init */
        *include_stack_ptr++ = file;
        file = f;
        /* add include file debug info */
        if (do_debug) {
            put_stabs(file->filename, N_BINCL, 0, 0, 0);
        }
        ch = '\n';
        goto the_end;
    } else if (tok == TOK_IFNDEF) {
        c = 1;
        goto do_ifdef;
    } else if (tok == TOK_IF) {
        c = expr_preprocess();
        goto do_if;
    } else if (tok == TOK_IFDEF) {
        c = 0;
    do_ifdef:
        next_nomacro();
        c = (sym_find1(&define_stack, tok) != 0) ^ c;
    do_if:
        if (ifdef_stack_ptr >= ifdef_stack + IFDEF_STACK_SIZE)
            error("memory full");
        *ifdef_stack_ptr++ = c;
        goto test_skip;
    } else if (tok == TOK_ELSE) {
        if (ifdef_stack_ptr == ifdef_stack)
            error("#else without matching #if");
        if (ifdef_stack_ptr[-1] & 2)
            error("#else after #else");
        c = (ifdef_stack_ptr[-1] ^= 3);
        goto test_skip;
    } else if (tok == TOK_ELIF) {
        if (ifdef_stack_ptr == ifdef_stack)
            error("#elif without matching #if");
        c = ifdef_stack_ptr[-1];
        if (c > 1)
            error("#elif after #else");
        /* last #if/#elif expression was true: we skip */
        if (c == 1)
            goto skip;
        c = expr_preprocess();
        ifdef_stack_ptr[-1] = c;
    test_skip:
        if (!(c & 1)) {
        skip:
            preprocess_skip();
            goto redo;
        }
    } else if (tok == TOK_ENDIF) {
        if (ifdef_stack_ptr == ifdef_stack)
            error("#endif without matching #if");
        ifdef_stack_ptr--;
    } else if (tok == TOK_LINE) {
        int line_num;
        next();
        if (tok != TOK_CINT)
            error("#line");
        line_num = tokc.i;
        next();
        if (tok != TOK_LINEFEED) {
            if (tok != TOK_STR)
                error("#line");
            pstrcpy(file->filename, sizeof(file->filename), 
                    (char *)tokc.cstr->data);
        }
        /* NOTE: we do it there to avoid problems with linefeed */
        file->line_num = line_num;
    } else if (tok == TOK_ERROR) {
        error("#error");
    }
    /* ignore other preprocess commands or #! for C scripts */
    while (tok != TOK_LINEFEED && tok != TOK_EOF)
        next_nomacro();
 the_end:
    return_linefeed = 0;
}

/* read a number in base b */
static int getn(int b)
{
    int n, t;
    n = 0;
    while (1) {
        if (ch >= 'a' && ch <= 'f')
            t = ch - 'a' + 10;
        else if (ch >= 'A' && ch <= 'F')
            t = ch - 'A' + 10;
        else if (isnum(ch))
            t = ch - '0';
        else
            break;
        if (t < 0 || t >= b)
            break;
        n = n * b + t;
        cinp();
    }
    return n;
}

/* read a character for string or char constant and eval escape codes */
static int getq(void)
{
    int c;

    c = ch;
    minp();
    if (c == '\\') {
        if (isnum(ch)) {
            /* at most three octal digits */
            c = ch - '0';
            minp();
            if (isnum(ch)) {
                c = c * 8 + ch - '0';
                minp();
                if (isnum(ch)) {
                    c = c * 8 + ch - '0';
                    minp();
                }
            }
            return c;
        } else if (ch == 'x') {
            minp();
            return getn(16);
        } else {
            if (ch == 'a')
                c = '\a';
            else if (ch == 'b')
                c = '\b';
            else if (ch == 'f')
                c = '\f';
            else if (ch == 'n')
                c = '\n';
            else if (ch == 'r')
                c = '\r';
            else if (ch == 't')
                c = '\t';
            else if (ch == 'v')
                c = '\v';
            else if (ch == 'e' && gnu_ext)
                c = 27;
            else if (ch == '\'' || ch == '\"' || ch == '\\' || ch == '?')
                c = ch;
            else
                error("invalid escaped char");
            minp();
        }
    } else if (c == '\r' && ch == '\n') {
        minp();
        c = '\n';
    }
    return c;
}

/* we use 64 bit numbers */
#define BN_SIZE 2

/* bn = (bn << shift) | or_val */
void bn_lshift(unsigned int *bn, int shift, int or_val)
{
    int i;
    unsigned int v;
    for(i=0;i<BN_SIZE;i++) {
        v = bn[i];
        bn[i] = (v << shift) | or_val;
        or_val = v >> (32 - shift);
    }
}

void bn_zero(unsigned int *bn)
{
    int i;
    for(i=0;i<BN_SIZE;i++) {
        bn[i] = 0;
    }
}

void parse_number(void)
{
    int b, t, shift, frac_bits, s, exp_val;
    char *q;
    unsigned int bn[BN_SIZE];
    double d;

    /* number */
    q = token_buf;
    t = ch;
    cinp();
    *q++ = t;
    b = 10;
    if (t == '.') {
        /* special dot handling */
        if (ch >= '0' && ch <= '9') {
            goto float_frac_parse;
        } else if (ch == '.') {
            cinp();
            if (ch != '.')
                expect("'.'");
            cinp();
            tok = TOK_DOTS;
        } else {
            /* dots */
            tok = t;
        }
        return;
    } else if (t == '0') {
        if (ch == 'x' || ch == 'X') {
            q--;
            cinp();
            b = 16;
        } else if (tcc_ext && (ch == 'b' || ch == 'B')) {
            q--;
            cinp();
            b = 2;
        }
    }
    /* parse all digits. cannot check octal numbers at this stage
       because of floating point constants */
    while (1) {
        if (ch >= 'a' && ch <= 'f')
            t = ch - 'a' + 10;
        else if (ch >= 'A' && ch <= 'F')
            t = ch - 'A' + 10;
        else if (isnum(ch))
            t = ch - '0';
        else
            break;
        if (t >= b)
            break;
        if (q >= token_buf + STRING_MAX_SIZE) {
        num_too_long:
            error("number too long");
        }
        *q++ = ch;
        cinp();
    }
    if (ch == '.' ||
        ((ch == 'e' || ch == 'E') && b == 10) ||
        ((ch == 'p' || ch == 'P') && (b == 16 || b == 2))) {
        if (b != 10) {
            /* NOTE: strtox should support that for hexa numbers, but
               non ISOC99 libcs do not support it, so we prefer to do
               it by hand */
            /* hexadecimal or binary floats */
            /* XXX: handle overflows */
            *q = '\0';
            if (b == 16)
                shift = 4;
            else 
                shift = 2;
            bn_zero(bn);
            q = token_buf;
            while (1) {
                t = *q++;
                if (t == '\0') {
                    break;
                } else if (t >= 'a') {
                    t = t - 'a' + 10;
                } else if (t >= 'A') {
                    t = t - 'A' + 10;
                } else {
                    t = t - '0';
                }
                bn_lshift(bn, shift, t);
            }
            frac_bits = 0;
            if (ch == '.') {
                cinp();
                while (1) {
                    t = ch;
                    if (t >= 'a' && t <= 'f') {
                        t = t - 'a' + 10;
                    } else if (t >= 'A' && t <= 'F') {
                        t = t - 'A' + 10;
                    } else if (t >= '0' && t <= '9') {
                        t = t - '0';
                    } else {
                        break;
                    }
                    if (t >= b)
                        error("invalid digit");
                    bn_lshift(bn, shift, t);
                    frac_bits += shift;
                    cinp();
                }
            }
            if (ch != 'p' && ch != 'P')
                error("exponent expected");
            cinp();
            s = 1;
            exp_val = 0;
            if (ch == '+') {
                cinp();
            } else if (ch == '-') {
                s = -1;
                cinp();
            }
            if (ch < '0' || ch > '9')
                error("exponent digits expected");
            while (ch >= '0' && ch <= '9') {
                exp_val = exp_val * 10 + ch - '0';
                cinp();
            }
            exp_val = exp_val * s;
            
            /* now we can generate the number */
            /* XXX: should patch directly float number */
            d = (double)bn[1] * 4294967296.0 + (double)bn[0];
            d = ldexp(d, exp_val - frac_bits);
            t = toup(ch);
            if (t == 'F') {
                cinp();
                tok = TOK_CFLOAT;
                /* float : should handle overflow */
                tokc.f = (float)d;
            } else if (t == 'L') {
                cinp();
                tok = TOK_CLDOUBLE;
                /* XXX: not large enough */
                tokc.ld = (long double)d;
            } else {
                tok = TOK_CDOUBLE;
                tokc.d = d;
            }
        } else {
            /* decimal floats */
            if (ch == '.') {
                if (q >= token_buf + STRING_MAX_SIZE)
                    goto num_too_long;
                *q++ = ch;
                cinp();
            float_frac_parse:
                while (ch >= '0' && ch <= '9') {
                    if (q >= token_buf + STRING_MAX_SIZE)
                        goto num_too_long;
                    *q++ = ch;
                    cinp();
                }
            }
            if (ch == 'e' || ch == 'E') {
                if (q >= token_buf + STRING_MAX_SIZE)
                    goto num_too_long;
                *q++ = ch;
                cinp();
                if (ch == '-' || ch == '+') {
                    if (q >= token_buf + STRING_MAX_SIZE)
                        goto num_too_long;
                    *q++ = ch;
                    cinp();
                }
                if (ch < '0' || ch > '9')
                    error("exponent digits expected");
                while (ch >= '0' && ch <= '9') {
                    if (q >= token_buf + STRING_MAX_SIZE)
                        goto num_too_long;
                    *q++ = ch;
                    cinp();
                }
            }
            *q = '\0';
            t = toup(ch);
            errno = 0;
            if (t == 'F') {
                cinp();
                tok = TOK_CFLOAT;
                tokc.f = strtof(token_buf, NULL);
            } else if (t == 'L') {
                cinp();
                tok = TOK_CLDOUBLE;
                tokc.ld = strtold(token_buf, NULL);
            } else {
                tok = TOK_CDOUBLE;
                tokc.d = strtod(token_buf, NULL);
            }
        }
    } else {
        unsigned long long n, n1;
        int lcount;

        /* integer number */
        *q = '\0';
        q = token_buf;
        if (b == 10 && *q == '0') {
            b = 8;
            q++;
        }
        n = 0;
        while(1) {
            t = *q++;
            /* no need for checks except for base 10 / 8 errors */
            if (t == '\0') {
                break;
            } else if (t >= 'a') {
                t = t - 'a' + 10;
            } else if (t >= 'A') {
                t = t - 'A' + 10;
            } else {
                t = t - '0';
                if (t >= b)
                    error("invalid digit");
            }
            n1 = n;
            n = n * b + t;
            /* detect overflow */
            if (n < n1)
                error("integer constant overflow");
        }
        
        /* XXX: not exactly ANSI compliant */
        if ((n & 0xffffffff00000000LL) != 0) {
            if ((n >> 63) != 0)
                tok = TOK_CULLONG;
            else
                tok = TOK_CLLONG;
        } else if (n > 0x7fffffff) {
            tok = TOK_CUINT;
        } else {
            tok = TOK_CINT;
        }
        lcount = 0;
        for(;;) {
            t = toup(ch);
            if (t == 'L') {
                if (lcount >= 2)
                    error("three 'l' in integer constant");
                lcount++;
                if (lcount == 2) {
                    if (tok == TOK_CINT)
                        tok = TOK_CLLONG;
                    else if (tok == TOK_CUINT)
                        tok = TOK_CULLONG;
                }
                cinp();
            } else if (t == 'U') {
                if (tok == TOK_CINT)
                    tok = TOK_CUINT;
                else if (tok == TOK_CLLONG)
                    tok = TOK_CULLONG;
                cinp();
            } else {
                break;
            }
        }
        if (tok == TOK_CINT || tok == TOK_CUINT)
            tokc.ui = n;
        else
            tokc.ull = n;
    }
}


/* return next token without macro substitution */
void next_nomacro1(void)
{
    int b;
    char *q;
    TokenSym *ts;

    /* skip spaces */
    while(1) {
        while (ch == '\n') {
            /* during preprocessor parsing, '\n' is a token */
            if (return_linefeed) {
                tok = TOK_LINEFEED;
                return;
            }
            cinp();
            skip_spaces();
            if (ch == '#') {
                /* preprocessor command if # at start of line after
                   spaces */
                preprocess();
            }
        }
        if (!is_space(ch))
            break;
        cinp();
    }
    if (isid(ch)) {
        q = token_buf;
        *q++ = ch;
        cinp();
        if (q[-1] == 'L') {
            if (ch == '\'') {
                tok = TOK_LCHAR;
                goto char_const;
            }
            if (ch == '\"') {
                tok = TOK_LSTR;
                goto str_const;
            }
        }
        while (isid(ch) || isnum(ch)) {
            if (q >= token_buf + STRING_MAX_SIZE)
                error("ident too long");
            *q++ = ch;
            cinp();
        }
        *q = '\0';
        ts = tok_alloc(token_buf, q - token_buf);
        tok = ts->tok;
    } else if (isnum(ch) || ch == '.') {
        parse_number();
    } else if (ch == '\'') {
        tok = TOK_CCHAR;
    char_const:
        minp();
        b = getq();
        /* this cast is needed if >= 128 */
        if (tok == TOK_CCHAR)
            b = (char)b; 
        tokc.i = b;
        if (ch != '\'')
            expect("\'");
        minp();
    } else if (ch == '\"') {
        tok = TOK_STR;
    str_const:
        minp();
        cstr_reset(&tokcstr);
        while (ch != '\"') {
            b = getq();
            if (ch == CH_EOF)
                error("unterminated string");
            if (tok == TOK_STR)
                cstr_ccat(&tokcstr, b);
            else
                cstr_wccat(&tokcstr, b);
        }
        if (tok == TOK_STR)
            cstr_ccat(&tokcstr, '\0');
        else
            cstr_wccat(&tokcstr, '\0');
        tokc.cstr = &tokcstr;
        minp();
    } else {
        q = tok_two_chars;
        /* two chars */
        tok = ch;
        cinp();
        while (*q) {
            if (*q == tok && q[1] == ch) {
                cinp();
                tok = q[2] & 0xff;
                /* three chars tests */
                if (tok == TOK_SHL || tok == TOK_SAR) {
                    if (ch == '=') {
                        tok = tok | 0x80;
                        cinp();
                    }
                } else if (tok == TOK_DOTS) {
                    if (ch != '.')
                        error("parse error");
                    cinp();
                }
                return;
            }
            q = q + 3;
        }
        /* single char substitutions */
        if (tok == '<')
            tok = TOK_LT;
        else if (tok == '>')
            tok = TOK_GT;
    }
}

/* return next token without macro substitution. Can read input from
   macro_ptr buffer */
void next_nomacro()
{
    if (macro_ptr) {
    redo:
        tok = *macro_ptr;
        if (tok) {
            tok = tok_get(&macro_ptr, &tokc);
            if (tok == TOK_LINENUM) {
                file->line_num = tokc.i;
                goto redo;
            }
        }
    } else {
        next_nomacro1();
    }
}

/* substitute args in macro_str and return allocated string */
int *macro_arg_subst(Sym **nested_list, int *macro_str, Sym *args)
{
    int *st, last_tok, t, notfirst;
    Sym *s;
    CValue cval;
    TokenString str;
    CString cstr;

    tok_str_new(&str);
    last_tok = 0;
    while(1) {
        t = tok_get(&macro_str, &cval);
        if (!t)
            break;
        if (t == '#') {
            /* stringize */
            t = tok_get(&macro_str, &cval);
            if (!t)
                break;
            s = sym_find2(args, t);
            if (s) {
                cstr_new(&cstr);
                st = (int *)s->c;
                notfirst = 0;
                while (*st) {
                    if (notfirst)
                        cstr_ccat(&cstr, ' ');
                    t = tok_get(&st, &cval);
                    cstr_cat(&cstr, get_tok_str(t, &cval));
                    notfirst = 1;
                }
                cstr_ccat(&cstr, '\0');
#ifdef PP_DEBUG
                printf("stringize: %s\n", (char *)cstr.data);
#endif
                /* add string */
                cval.cstr = &cstr;
                tok_str_add2(&str, TOK_STR, &cval);
                cstr_free(&cstr);
            } else {
                tok_str_add2(&str, t, &cval);
            }
        } else if (t >= TOK_IDENT) {
            s = sym_find2(args, t);
            if (s) {
                st = (int *)s->c;
                /* if '##' is present before or after, no arg substitution */
                if (*macro_str == TOK_TWOSHARPS || last_tok == TOK_TWOSHARPS) {
                    /* special case for var arg macros : ## eats the
                       ',' if empty VA_ARGS riable. */
                    /* XXX: test of the ',' is not 100%
                       reliable. should fix it to avoid security
                       problems */
                    if (gnu_ext && s->t && *st == 0 &&
                        last_tok == TOK_TWOSHARPS && 
                        str.len >= 2 && str.str[str.len - 2] == ',') {
                        /* suppress ',' '##' */
                        str.len -= 2;
                    } else {
                        int t1;
                        for(;;) {
                            t1 = tok_get(&st, &cval);
                            if (!t1)
                                break;
                            tok_str_add2(&str, t1, &cval);
                        }
                    }
                } else {
                    macro_subst(&str, nested_list, st);
                }
            } else {
                tok_str_add(&str, t);
            }
        } else {
            tok_str_add2(&str, t, &cval);
        }
        last_tok = t;
    }
    tok_str_add(&str, 0);
    return str.str;
}

/* handle the '##' operator */
int *macro_twosharps(int *macro_str)
{
    TokenSym *ts;
    int *macro_ptr1;
    int t;
    char *p;
    CValue cval;
    TokenString macro_str1;
    
    tok_str_new(&macro_str1);
    tok = 0;
    while (1) {
        next_nomacro();
        if (tok == 0)
            break;
        while (*macro_ptr == TOK_TWOSHARPS) {
            macro_ptr++;
            macro_ptr1 = macro_ptr;
            t = *macro_ptr;
            if (t) {
                t = tok_get(&macro_ptr, &cval);
                /* XXX: we handle only most common cases: 
                   ident + ident or ident + number */
                if (tok >= TOK_IDENT && 
                    (t >= TOK_IDENT || t == TOK_CINT)) {
                    p = get_tok_str(tok, &tokc);
                    pstrcpy(token_buf, sizeof(token_buf), p);
                    p = get_tok_str(t, &cval);
                    pstrcat(token_buf, sizeof(token_buf), p);
                    ts = tok_alloc(token_buf, 0);
                    tok = ts->tok; /* modify current token */
                } else {
                    /* cannot merge tokens: skip '##' */
                    macro_ptr = macro_ptr1;
                    break;
                }
            }
        }
        tok_str_add2(&macro_str1, tok, &tokc);
    }
    tok_str_add(&macro_str1, 0);
    return macro_str1.str;
}

/* do macro substitution of macro_str and add result to
   (tok_str,tok_len). If macro_str is NULL, then input stream token is
   substituted. 'nested_list' is the list of all macros we got inside
   to avoid recursing. */
void macro_subst(TokenString *tok_str,
                 Sym **nested_list, int *macro_str)
{
    Sym *s, *args, *sa, *sa1;
    int parlevel, *mstr, t, *saved_macro_ptr;
    int mstr_allocated, *macro_str1;
    CString cstr;
    CValue cval;
    TokenString str;
    char *cstrval;

    saved_macro_ptr = macro_ptr;
    macro_ptr = macro_str;
    macro_str1 = NULL;
    if (macro_str) {
        /* first scan for '##' operator handling */
        macro_str1 = macro_twosharps(macro_str);
        macro_ptr = macro_str1;
    }

    while (1) {
        next_nomacro();
        if (tok == 0)
            break;
        if ((s = sym_find1(&define_stack, tok)) != NULL) {
            /* if symbol is a macro, prepare substitution */
            /* if nested substitution, do nothing */
            if (sym_find2(*nested_list, tok))
                goto no_subst;

            /* special macros */
            if (tok == TOK___LINE__) {
                cval.i = file->line_num;
                tok_str_add2(tok_str, TOK_CINT, &cval);
            } else if (tok == TOK___FILE__) {
                cstrval = file->filename;
                goto add_cstr;
                tok_str_add2(tok_str, TOK_STR, &cval);
            } else if (tok == TOK___DATE__) {
                cstrval = "Jan  1 2002";
                goto add_cstr;
            } else if (tok == TOK___TIME__) {
                cstrval = "00:00:00";
                goto add_cstr;
            } else if (tok == TOK___FUNCTION__) {
                cstrval = funcname;
            add_cstr:
                cstr_new(&cstr);
                cstr_cat(&cstr, cstrval);
                cstr_ccat(&cstr, '\0');
                cval.cstr = &cstr;
                tok_str_add2(tok_str, TOK_STR, &cval);
                cstr_free(&cstr);
            } else {
                mstr = (int *)s->c;
                mstr_allocated = 0;
                if (s->t == MACRO_FUNC) {
                    /* NOTE: we do not use next_nomacro to avoid eating the
                       next token. XXX: find better solution */
                    if (macro_ptr) {
                        t = *macro_ptr;
                    } else {
                        while (is_space(ch) || ch == '\n')
                            cinp();
                        t = ch;
                    }
                    if (t != '(') /* no macro subst */
                        goto no_subst;
                    
                /* argument macro */
                    next_nomacro();
                    next_nomacro();
                    args = NULL;
                    sa = s->next;
                    /* NOTE: empty args are allowed, except if no args */
                    for(;;) {
                        /* handle '()' case */
                        if (!args && tok == ')')
                            break;
                        if (!sa)
                            error("macro '%s' used with too many args",
                                  get_tok_str(s->v, 0));
                        tok_str_new(&str);
                        parlevel = 0;
                        /* NOTE: non zero sa->t indicates VA_ARGS */
                        while ((parlevel > 0 || 
                                (tok != ')' && 
                                 (tok != ',' || sa->t))) && 
                               tok != -1) {
                            if (tok == '(')
                                parlevel++;
                            else if (tok == ')')
                                parlevel--;
                            tok_str_add2(&str, tok, &tokc);
                            next_nomacro();
                        }
                        tok_str_add(&str, 0);
                        sym_push2(&args, sa->v & ~SYM_FIELD, sa->t, (int)str.str);
                        sa = sa->next;
                        if (tok == ')') {
                            /* special case for gcc var args: add an empty
                               var arg argument if it is omitted */
                            if (sa && sa->t && gnu_ext)
                                continue;
                            else
                                break;
                        }
                        if (tok != ',')
                            expect(",");
                        next_nomacro();
                    }
                    if (sa) {
                        error("macro '%s' used with too few args",
                              get_tok_str(s->v, 0));
                    }

                    /* now subst each arg */
                    mstr = macro_arg_subst(nested_list, mstr, args);
                    /* free memory */
                    sa = args;
                    while (sa) {
                        sa1 = sa->prev;
                        tok_str_free((int *)sa->c);
                        tcc_free(sa);
                        sa = sa1;
                    }
                    mstr_allocated = 1;
                }
                sym_push2(nested_list, s->v, 0, 0);
                macro_subst(tok_str, nested_list, mstr);
                /* pop nested defined symbol */
                sa1 = *nested_list;
                *nested_list = sa1->prev;
                tcc_free(sa1);
                if (mstr_allocated)
                    tok_str_free(mstr);
            }
        } else {
        no_subst:
            /* no need to add if reading input stream */
            if (!macro_str)
                return;
            tok_str_add2(tok_str, tok, &tokc);
        }
        /* only replace one macro while parsing input stream */
        if (!macro_str)
            return;
    }
    macro_ptr = saved_macro_ptr;
    if (macro_str1)
        tok_str_free(macro_str1);
}

/* return next token with macro substitution */
void next(void)
{
    Sym *nested_list;
    TokenString str;

    /* special 'ungettok' case for label parsing */
    if (tok1) {
        tok = tok1;
        tokc = tok1c;
        tok1 = 0;
    } else {
    redo:
        if (!macro_ptr) {
            /* if not reading from macro substituted string, then try
               to substitute */
            /* XXX: optimize non macro case */
            tok_str_new(&str);
            nested_list = NULL;
            macro_subst(&str, &nested_list, NULL);
            if (str.str) {
                tok_str_add(&str, 0);
                macro_ptr = str.str;
                macro_ptr_allocated = str.str;
                goto redo;
            }
            if (tok == 0)
                goto redo;
        } else {
            next_nomacro();
            if (tok == 0) {
                /* end of macro string: free it */
                tok_str_free(macro_ptr_allocated);
                macro_ptr = NULL;
                goto redo;
            }
        }
    }
#if defined(DEBUG)
    printf("token = %s\n", get_tok_str(tok, &tokc));
#endif
}

void swap(int *p, int *q)
{
    int t;
    t = *p;
    *p = *q;
    *q = t;
}

void vsetc(int t, int r, CValue *vc)
{
    if (vtop >= vstack + VSTACK_SIZE)
        error("memory full");
    /* cannot let cpu flags if other instruction are generated */
    /* XXX: VT_JMP test too ? */
    if ((vtop->r & VT_VALMASK) == VT_CMP)
        gv(RC_INT);
    vtop++;
    vtop->t = t;
    vtop->r = r;
    vtop->r2 = VT_CONST;
    vtop->c = *vc;
}

/* push integer constant */
void vpushi(int v)
{
    CValue cval;
    cval.i = v;
    vsetc(VT_INT, VT_CONST, &cval);
}

/* Return a static symbol pointing to a section */
static Sym *get_sym_ref(int t, Section *sec, 
                        unsigned long offset, unsigned long size)
{
    int v;
    Sym *sym;

    v = anon_sym++;
    sym = sym_push1(&global_stack, v, t | VT_STATIC, 0);
    sym->r = VT_CONST | VT_SYM;
    put_extern_sym(sym, sec, offset, size);
    return sym;
}

/* push a reference to a section offset by adding a dummy symbol */
static void vpush_ref(int t, Section *sec, unsigned long offset, unsigned long size)
{
    CValue cval;

    cval.ul = 0;
    vsetc(t, VT_CONST | VT_SYM, &cval);
    vtop->sym = get_sym_ref(t, sec, offset, size);
}

/* define a new external reference to a symbol 'v' of type 'u' */
static Sym *external_global_sym(int v, int u, int r)
{
    Sym *s;

    s = sym_find(v);
    if (!s) {
        /* push forward reference */
        s = sym_push1(&global_stack, 
                      v, u | VT_EXTERN, 0);
        s->r = r | VT_CONST | VT_SYM;
    }
    return s;
}

/* define a new external reference to a symbol 'v' of type 'u' */
static Sym *external_sym(int v, int u, int r)
{
    Sym *s;

    s = sym_find(v);
    if (!s) {
        /* push forward reference */
        s = sym_push(v, u | VT_EXTERN, r | VT_CONST | VT_SYM, 0);
    }
    return s;
}

/* push a reference to global symbol v */
static void vpush_global_sym(int t, int v)
{
    Sym *sym;
    CValue cval;

    sym = external_global_sym(v, t, 0);
    cval.ul = 0;
    vsetc(t, VT_CONST | VT_SYM, &cval);
    vtop->sym = sym;
}

void vset(int t, int r, int v)
{
    CValue cval;

    cval.i = v;
    vsetc(t, r, &cval);
}

void vswap(void)
{
    SValue tmp;

    tmp = vtop[0];
    vtop[0] = vtop[-1];
    vtop[-1] = tmp;
}

void vpushv(SValue *v)
{
    if (vtop >= vstack + VSTACK_SIZE)
        error("memory full");
    vtop++;
    *vtop = *v;
}

void vdup(void)
{
    vpushv(vtop);
}

/* save r to the memory stack, and mark it as being free */
void save_reg(int r)
{
    int l, saved, t, size, align;
    SValue *p, sv;

    /* modify all stack values */
    saved = 0;
    l = 0;
    for(p=vstack;p<=vtop;p++) {
        if ((p->r & VT_VALMASK) == r ||
            (p->r2 & VT_VALMASK) == r) {
            /* must save value on stack if not already done */
            if (!saved) {
                /* store register in the stack */
                t = p->t;
                if ((p->r & VT_LVAL) || 
                    (!is_float(t) && (t & VT_BTYPE) != VT_LLONG))
                    t = VT_INT;
                size = type_size(t, &align);
                loc = (loc - size) & -align;
                sv.t = t;
                sv.r = VT_LOCAL | VT_LVAL;
                sv.c.ul = loc;
                store(r, &sv);
#ifdef TCC_TARGET_I386
                /* x86 specific: need to pop fp register ST0 if saved */
                if (r == REG_ST0) {
                    o(0xd9dd); /* fstp %st(1) */
                }
#endif
                /* special long long case */
                if ((t & VT_BTYPE) == VT_LLONG) {
                    sv.c.ul += 4;
                    store(p->r2, &sv);
                }
                l = loc;
                saved = 1;
            }
            /* mark that stack entry as being saved on the stack */
            if (p->r & VT_LVAL) {
                /* also suppress the bounded flag because the
                   relocation address of the function was stored in
                   p->c.ul */
                p->r = (p->r & ~(VT_VALMASK | VT_BOUNDED)) | VT_LLOCAL;
            } else {
                p->r = lvalue_type(p->t) | VT_LOCAL;
            }
            p->r2 = VT_CONST;
            p->c.ul = l;
        }
    }
}

/* find a free register of class 'rc'. If none, save one register */
int get_reg(int rc)
{
    int r;
    SValue *p;

    /* find a free register */
    for(r=0;r<NB_REGS;r++) {
        if (reg_classes[r] & rc) {
            for(p=vstack;p<=vtop;p++) {
                if ((p->r & VT_VALMASK) == r ||
                    (p->r2 & VT_VALMASK) == r)
                    goto notfound;
            }
            return r;
        }
    notfound: ;
    }
    
    /* no register left : free the first one on the stack (VERY
       IMPORTANT to start from the bottom to ensure that we don't
       spill registers used in gen_opi()) */
    for(p=vstack;p<=vtop;p++) {
        r = p->r & VT_VALMASK;
        if (r < VT_CONST && (reg_classes[r] & rc)) {
            save_reg(r);
            break;
        }
    }
    return r;
}

/* save registers up to (vtop - n) stack entry */
void save_regs(int n)
{
    int r;
    SValue *p, *p1;
    p1 = vtop - n;
    for(p = vstack;p <= p1; p++) {
        r = p->r & VT_VALMASK;
        if (r < VT_CONST) {
            save_reg(r);
        }
    }
}

/* move register 's' to 'r', and flush previous value of r to memory
   if needed */
void move_reg(int r, int s)
{
    SValue sv;

    if (r != s) {
        save_reg(r);
        sv.t = VT_INT;
        sv.r = s;
        sv.c.ul = 0;
        load(r, &sv);
    }
}

/* get address of vtop (vtop MUST BE an lvalue) */
void gaddrof(void)
{
    vtop->r &= ~VT_LVAL;
    /* tricky: if saved lvalue, then we can go back to lvalue */
    if ((vtop->r & VT_VALMASK) == VT_LLOCAL)
        vtop->r = (vtop->r & ~(VT_VALMASK | VT_LVAL_TYPE)) | VT_LOCAL | VT_LVAL;
}

#ifdef CONFIG_TCC_BCHECK
/* generate lvalue bound code */
void gbound(void)
{
    int lval_type, t1;

    vtop->r &= ~VT_MUSTBOUND;
    /* if lvalue, then use checking code before dereferencing */
    if (vtop->r & VT_LVAL) {
        /* if not VT_BOUNDED value, then make one */
        if (!(vtop->r & VT_BOUNDED)) {
            lval_type = vtop->r & (VT_LVAL_TYPE | VT_LVAL);
            /* must save type because we must set it to int to get pointer */
            t1 = vtop->t;
            vtop->t = VT_INT;
            gaddrof();
            vpushi(0);
            gen_bounded_ptr_add();
            vtop->r |= lval_type;
            vtop->t = t1;
        }
        /* then check for dereferencing */
        gen_bounded_ptr_deref();
    }
}
#endif

/* store vtop a register belonging to class 'rc'. lvalues are
   converted to values. Cannot be used if cannot be converted to
   register value (such as structures). */
int gv(int rc)
{
    int r, r2, rc2, bit_pos, bit_size, size, align, i;
    unsigned long long ll;

    /* NOTE: get_reg can modify vstack[] */
    if (vtop->t & VT_BITFIELD) {
        bit_pos = (vtop->t >> VT_STRUCT_SHIFT) & 0x3f;
        bit_size = (vtop->t >> (VT_STRUCT_SHIFT + 6)) & 0x3f;
        /* remove bit field info to avoid loops */
        vtop->t &= ~(VT_BITFIELD | (-1 << VT_STRUCT_SHIFT));
        /* generate shifts */
        vpushi(32 - (bit_pos + bit_size));
        gen_op(TOK_SHL);
        vpushi(32 - bit_size);
        /* NOTE: transformed to SHR if unsigned */
        gen_op(TOK_SAR);
        r = gv(rc);
    } else {
        if (is_float(vtop->t) && 
            (vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
            Sym *sym;
            int *ptr;
            unsigned long offset;
            
            /* XXX: unify with initializers handling ? */
            /* CPUs usually cannot use float constants, so we store them
               generically in data segment */
            size = type_size(vtop->t, &align);
            offset = (data_section->data_offset + align - 1) & -align;
            data_section->data_offset = offset;
            /* XXX: not portable yet */
            ptr = section_ptr_add(data_section, size);
            size = size >> 2;
            for(i=0;i<size;i++)
                ptr[i] = vtop->c.tab[i];
            sym = get_sym_ref(vtop->t, data_section, offset, size << 2);
            vtop->r |= VT_LVAL | VT_SYM;
            vtop->sym = sym;
            vtop->c.ul = 0;
        }
#ifdef CONFIG_TCC_BCHECK
        if (vtop->r & VT_MUSTBOUND) 
            gbound();
#endif

        r = vtop->r & VT_VALMASK;
        /* need to reload if:
           - constant
           - lvalue (need to dereference pointer)
           - already a register, but not in the right class */
        if (r >= VT_CONST || 
            (vtop->r & VT_LVAL) ||
            !(reg_classes[r] & rc) ||
            ((vtop->t & VT_BTYPE) == VT_LLONG && 
             !(reg_classes[vtop->r2] & rc))) {
            r = get_reg(rc);
            if ((vtop->t & VT_BTYPE) == VT_LLONG) {
                /* two register type load : expand to two words
                   temporarily */
                if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
                    /* load constant */
                    ll = vtop->c.ull;
                    vtop->c.ui = ll; /* first word */
                    load(r, vtop);
                    vtop->r = r; /* save register value */
                    vpushi(ll >> 32); /* second word */
                } else if (r >= VT_CONST || 
                           (vtop->r & VT_LVAL)) {
                    /* load from memory */
                    load(r, vtop);
                    vdup();
                    vtop[-1].r = r; /* save register value */
                    /* increment pointer to get second word */
                    vtop->t = VT_INT;
                    gaddrof();
                    vpushi(4);
                    gen_op('+');
                    vtop->r |= VT_LVAL;
                } else {
                    /* move registers */
                    load(r, vtop);
                    vdup();
                    vtop[-1].r = r; /* save register value */
                    vtop->r = vtop[-1].r2;
                }
                /* allocate second register */
                rc2 = RC_INT;
                if (rc == RC_IRET)
                    rc2 = RC_LRET;
                r2 = get_reg(rc2);
                load(r2, vtop);
                vpop();
                /* write second register */
                vtop->r2 = r2;
            } else if ((vtop->r & VT_LVAL) && !is_float(vtop->t)) {
                int t1, t;
                /* lvalue of scalar type : need to use lvalue type
                   because of possible cast */
                t = vtop->t;
                t1 = t;
                /* compute memory access type */
                if (vtop->r & VT_LVAL_BYTE)
                    t = VT_BYTE;
                else if (vtop->r & VT_LVAL_SHORT)
                    t = VT_SHORT;
                if (vtop->r & VT_LVAL_UNSIGNED)
                    t |= VT_UNSIGNED;
                vtop->t = t;
                load(r, vtop);
                /* restore wanted type */
                vtop->t = t1;
            } else {
                /* one register type load */
                load(r, vtop);
            }
        }
        vtop->r = r;
    }
    return r;
}

/* generate vtop[-1] and vtop[0] in resp. classes rc1 and rc2 */
void gv2(int rc1, int rc2)
{
    /* generate more generic register first */
    if (rc1 <= rc2) {
        vswap();
        gv(rc1);
        vswap();
        gv(rc2);
        /* test if reload is needed for first register */
        if ((vtop[-1].r & VT_VALMASK) >= VT_CONST) {
            vswap();
            gv(rc1);
            vswap();
        }
    } else {
        gv(rc2);
        vswap();
        gv(rc1);
        vswap();
        /* test if reload is needed for first register */
        if ((vtop[0].r & VT_VALMASK) >= VT_CONST) {
            gv(rc2);
        }
    }
}

/* expand long long on stack in two int registers */
void lexpand(void)
{
    int u;

    u = vtop->t & VT_UNSIGNED;
    gv(RC_INT);
    vdup();
    vtop[0].r = vtop[-1].r2;
    vtop[0].r2 = VT_CONST;
    vtop[-1].r2 = VT_CONST;
    vtop[0].t = VT_INT | u;
    vtop[-1].t = VT_INT | u;
}

/* build a long long from two ints */
void lbuild(int t)
{
    gv2(RC_INT, RC_INT);
    vtop[-1].r2 = vtop[0].r;
    vtop[-1].t = t;
    vpop();
}

/* rotate n first stack elements to the bottom */
void vrotb(int n)
{
    int i;
    SValue tmp;

    tmp = vtop[-n + 1];
    for(i=-n+1;i!=0;i++)
        vtop[i] = vtop[i+1];
    vtop[0] = tmp;
}

/* pop stack value */
void vpop(void)
{
    int v;
    v = vtop->r & VT_VALMASK;
#ifdef TCC_TARGET_I386
    /* for x86, we need to pop the FP stack */
    if (v == REG_ST0) {
        o(0xd9dd); /* fstp %st(1) */
    } else
#endif
    if (v == VT_JMP || v == VT_JMPI) {
        /* need to put correct jump if && or || without test */
        gsym(vtop->c.ul);
    }
    vtop--;
}

/* convert stack entry to register and duplicate its value in another
   register */
void gv_dup(void)
{
    int rc, t, r, r1;
    SValue sv;

    t = vtop->t;
    if ((t & VT_BTYPE) == VT_LLONG) {
        lexpand();
        gv_dup();
        vswap();
        vrotb(3);
        gv_dup();
        vrotb(4);
        /* stack: H L L1 H1 */
        lbuild(t);
        vrotb(3);
        vrotb(3);
        vswap();
        lbuild(t);
        vswap();
    } else {
        /* duplicate value */
        rc = RC_INT;
        sv.t = VT_INT;
        if (is_float(t)) {
            rc = RC_FLOAT;
            sv.t = t;
        }
        r = gv(rc);
        r1 = get_reg(rc);
        sv.r = r;
        sv.c.ul = 0;
        load(r1, &sv); /* move r to r1 */
        vdup();
        /* duplicates value */
        vtop->r = r1;
    }
}

/* generate CPU independent (unsigned) long long operations */
void gen_opl(int op)
{
    int t, a, b, op1, c, i;
    int func;
    GFuncContext gf;
    SValue tmp;

    switch(op) {
    case '/':
    case TOK_PDIV:
        func = TOK___divdi3;
        goto gen_func;
    case TOK_UDIV:
        func = TOK___udivdi3;
        goto gen_func;
    case '%':
        func = TOK___moddi3;
        goto gen_func;
    case TOK_UMOD:
        func = TOK___umoddi3;
    gen_func:
        /* call generic long long function */
        gfunc_start(&gf, FUNC_CDECL);
        gfunc_param(&gf);
        gfunc_param(&gf);
        vpush_global_sym(func_old_type, func);
        gfunc_call(&gf);
        vpushi(0);
        vtop->r = REG_IRET;
        vtop->r2 = REG_LRET;
        break;
    case '^':
    case '&':
    case '|':
    case '*':
    case '+':
    case '-':
        t = vtop->t;
        vswap();
        lexpand();
        vrotb(3);
        lexpand();
        /* stack: L1 H1 L2 H2 */
        tmp = vtop[0];
        vtop[0] = vtop[-3];
        vtop[-3] = tmp;
        tmp = vtop[-2];
        vtop[-2] = vtop[-3];
        vtop[-3] = tmp;
        vswap();
        /* stack: H1 H2 L1 L2 */
        if (op == '*') {
            vpushv(vtop - 1);
            vpushv(vtop - 1);
            gen_op(TOK_UMULL);
            lexpand();
            /* stack: H1 H2 L1 L2 ML MH */
            for(i=0;i<4;i++)
                vrotb(6);
            /* stack: ML MH H1 H2 L1 L2 */
            tmp = vtop[0];
            vtop[0] = vtop[-2];
            vtop[-2] = tmp;
            /* stack: ML MH H1 L2 H2 L1 */
            gen_op('*');
            vrotb(3);
            vrotb(3);
            gen_op('*');
            /* stack: ML MH M1 M2 */
            gen_op('+');
            gen_op('+');
        } else if (op == '+' || op == '-') {
            /* XXX: add non carry method too (for MIPS or alpha) */
            if (op == '+')
                op1 = TOK_ADDC1;
            else
                op1 = TOK_SUBC1;
            gen_op(op1);
            /* stack: H1 H2 (L1 op L2) */
            vrotb(3);
            vrotb(3);
            gen_op(op1 + 1); /* TOK_xxxC2 */
        } else {
            gen_op(op);
            /* stack: H1 H2 (L1 op L2) */
            vrotb(3);
            vrotb(3);
            /* stack: (L1 op L2) H1 H2 */
            gen_op(op);
            /* stack: (L1 op L2) (H1 op H2) */
        }
        /* stack: L H */
        lbuild(t);
        break;
    case TOK_SAR:
    case TOK_SHR:
    case TOK_SHL:
        if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) {
            t = vtop[-1].t;
            vswap();
            lexpand();
            vrotb(3);
        /* stack: L H shift */
            c = (int)vtop->c.i;
            /* constant: simpler */
            /* NOTE: all comments are for SHL. the other cases are
               done by swaping words */
            vpop();
            if (op != TOK_SHL)
                vswap();
            if (c >= 32) {
                /* stack: L H */
                vpop();
                if (c > 32) {
                    vpushi(c - 32);
                    gen_op(op);
                }
                if (op != TOK_SAR) {
                    vpushi(0);
                } else {
                    gv_dup();
                    vpushi(31);
                    gen_op(TOK_SAR);
                }
                vswap();
            } else {
                vswap();
                gv_dup();
                /* stack: H L L */
                vpushi(c);
                gen_op(op);
                vswap();
                vpushi(32 - c);
                if (op == TOK_SHL)
                    gen_op(TOK_SHR);
                else
                    gen_op(TOK_SHL);
                vrotb(3);
                /* stack: L L H */
                vpushi(c);
                gen_op(op);
                gen_op('|');
            }
            if (op != TOK_SHL)
                vswap();
            lbuild(t);
        } else {
            /* XXX: should provide a faster fallback on x86 ? */
            switch(op) {
            case TOK_SAR:
                func = TOK___sardi3;
                goto gen_func;
            case TOK_SHR:
                func = TOK___shrdi3;
                goto gen_func;
            case TOK_SHL:
                func = TOK___shldi3;
                goto gen_func;
            }
        }
        break;
    default:
        /* compare operations */
        t = vtop->t;
        vswap();
        lexpand();
        vrotb(3);
        lexpand();
        /* stack: L1 H1 L2 H2 */
        tmp = vtop[-1];
        vtop[-1] = vtop[-2];
        vtop[-2] = tmp;
        /* stack: L1 L2 H1 H2 */
        /* compare high */
        op1 = op;
        /* when values are equal, we need to compare low words. since
           the jump is inverted, we invert the test too. */
        if (op1 == TOK_LT)
            op1 = TOK_LE;
        else if (op1 == TOK_GT)
            op1 = TOK_GE;
        else if (op1 == TOK_ULT)
            op1 = TOK_ULE;
        else if (op1 == TOK_UGT)
            op1 = TOK_UGE;
        a = 0;
        b = 0;
        gen_op(op1);
        if (op1 != TOK_NE) {
            a = gtst(1, 0);
        }
        if (op != TOK_EQ) {
            /* generate non equal test */
            /* XXX: NOT PORTABLE yet */
            if (a == 0) {
                b = gtst(0, 0);
            } else {
#ifdef TCC_TARGET_I386
                b = psym(0x850f, 0);
#else
                error("not implemented");
#endif
            }
        }
        /* compare low */
        gen_op(op);
        a = gtst(1, a);
        gsym(b);
        vset(VT_INT, VT_JMPI, a);
        break;
    }
}

/* handle integer constant optimizations and various machine
   independant opt */
void gen_opic(int op)
{
    int fc, c1, c2, n;
    SValue *v1, *v2;

    v1 = vtop - 1;
    v2 = vtop;
    /* currently, we cannot do computations with forward symbols */
    c1 = (v1->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST;
    c2 = (v2->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST;
    if (c1 && c2) {
        fc = v2->c.i;
        switch(op) {
        case '+': v1->c.i += fc; break;
        case '-': v1->c.i -= fc; break;
        case '&': v1->c.i &= fc; break;
        case '^': v1->c.i ^= fc; break;
        case '|': v1->c.i |= fc; break;
        case '*': v1->c.i *= fc; break;

        case TOK_PDIV:
        case '/':
        case '%':
        case TOK_UDIV:
        case TOK_UMOD:
            /* if division by zero, generate explicit division */
            if (fc == 0) {
                if (const_wanted)
                    error("division by zero in constant");
                goto general_case;
            }
            switch(op) {
            default: v1->c.i /= fc; break;
            case '%': v1->c.i %= fc; break;
            case TOK_UDIV: v1->c.i = (unsigned)v1->c.i / fc; break;
            case TOK_UMOD: v1->c.i = (unsigned)v1->c.i % fc; break;
            }
            break;
        case TOK_SHL: v1->c.i <<= fc; break;
        case TOK_SHR: v1->c.i = (unsigned)v1->c.i >> fc; break;
        case TOK_SAR: v1->c.i >>= fc; break;
            /* tests */
        case TOK_ULT: v1->c.i = (unsigned)v1->c.i < (unsigned)fc; break;
        case TOK_UGE: v1->c.i = (unsigned)v1->c.i >= (unsigned)fc; break;
        case TOK_EQ: v1->c.i = v1->c.i == fc; break;
        case TOK_NE: v1->c.i = v1->c.i != fc; break;
        case TOK_ULE: v1->c.i = (unsigned)v1->c.i <= (unsigned)fc; break;
        case TOK_UGT: v1->c.i = (unsigned)v1->c.i > (unsigned)fc; break;
        case TOK_LT: v1->c.i = v1->c.i < fc; break;
        case TOK_GE: v1->c.i = v1->c.i >= fc; break;
        case TOK_LE: v1->c.i = v1->c.i <= fc; break;
        case TOK_GT: v1->c.i = v1->c.i > fc; break;
            /* logical */
        case TOK_LAND: v1->c.i = v1->c.i && fc; break;
        case TOK_LOR: v1->c.i = v1->c.i || fc; break;
        default:
            goto general_case;
        }
        vtop--;
    } else {
        /* if commutative ops, put c2 as constant */
        if (c1 && (op == '+' || op == '&' || op == '^' || 
                   op == '|' || op == '*')) {
            vswap();
            swap(&c1, &c2);
        }
        fc = vtop->c.i;
        if (c2 && (((op == '*' || op == '/' || op == TOK_UDIV || 
                     op == TOK_PDIV) && 
                    fc == 1) ||
                   ((op == '+' || op == '-' || op == '|' || op == '^' || 
                     op == TOK_SHL || op == TOK_SHR || op == TOK_SAR) && 
                    fc == 0) ||
                   (op == '&' && 
                    fc == -1))) {
            /* nothing to do */
            vtop--;
        } else if (c2 && (op == '*' || op == TOK_PDIV || op == TOK_UDIV)) {
            /* try to use shifts instead of muls or divs */
            if (fc > 0 && (fc & (fc - 1)) == 0) {
                n = -1;
                while (fc) {
                    fc >>= 1;
                    n++;
                }
                vtop->c.i = n;
                if (op == '*')
                    op = TOK_SHL;
                else if (op == TOK_PDIV)
                    op = TOK_SAR;
                else
                    op = TOK_SHR;
            }
            goto general_case;
        } else if (c2 && (op == '+' || op == '-') &&
                   (vtop[-1].r & (VT_VALMASK | VT_LVAL | VT_SYM)) == 
                   (VT_CONST | VT_SYM)) {
            /* symbol + constant case */
            if (op == '-')
                fc = -fc;
            vtop--;
            vtop->c.i += fc;
        } else {
        general_case:
            /* call low level op generator */
            gen_opi(op);
        }
    }
}

/* generate a floating point operation with constant propagation */
void gen_opif(int op)
{
    int c1, c2;
    SValue *v1, *v2;
    long double f1, f2;

    v1 = vtop - 1;
    v2 = vtop;
    /* currently, we cannot do computations with forward symbols */
    c1 = (v1->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST;
    c2 = (v2->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST;
    if (c1 && c2) {
        if (v1->t == VT_FLOAT) {
            f1 = v1->c.f;
            f2 = v2->c.f;
        } else if (v1->t == VT_DOUBLE) {
            f1 = v1->c.d;
            f2 = v2->c.d;
        } else {
            f1 = v1->c.ld;
            f2 = v2->c.ld;
        }

        /* NOTE: we only do constant propagation if finite number (not
           NaN or infinity) (ANSI spec) */
        if (!ieee_finite(f1) || !ieee_finite(f2))
            goto general_case;

        switch(op) {
        case '+': f1 += f2; break;
        case '-': f1 -= f2; break;
        case '*': f1 *= f2; break;
        case '/': 
            if (f2 == 0.0) {
                if (const_wanted)
                    error("division by zero in constant");
                goto general_case;
            }
            f1 /= f2; 
            break;
            /* XXX: also handles tests ? */
        default:
            goto general_case;
        }
        /* XXX: overflow test ? */
        if (v1->t == VT_FLOAT) {
            v1->c.f = f1;
        } else if (v1->t == VT_DOUBLE) {
            v1->c.d = f1;
        } else {
            v1->c.ld = f1;
        }
        vtop--;
    } else {
    general_case:
        gen_opf(op);
    }
}


int pointed_size(int t)
{
    return type_size(pointed_type(t), &t);
}

#if 0
void check_pointer_types(SValue *p1, SValue *p2)
{
    char buf1[256], buf2[256];
    int t1, t2;
    t1 = p1->t;
    t2 = p2->t;
    if (!is_compatible_types(t1, t2)) {
        type_to_str(buf1, sizeof(buf1), t1, NULL);
        type_to_str(buf2, sizeof(buf2), t2, NULL);
        error("incompatible pointers '%s' and '%s'", buf1, buf2);
    }
}
#endif

/* generic gen_op: handles types problems */
void gen_op(int op)
{
    int u, t1, t2, bt1, bt2, t;

    t1 = vtop[-1].t;
    t2 = vtop[0].t;
    bt1 = t1 & VT_BTYPE;
    bt2 = t2 & VT_BTYPE;
        
    if (bt1 == VT_PTR || bt2 == VT_PTR) {
        /* at least one operand is a pointer */
        /* relationnal op: must be both pointers */
        if (op >= TOK_ULT && op <= TOK_GT) {
            //            check_pointer_types(vtop, vtop - 1);
            /* pointers are handled are unsigned */
            t = VT_INT | VT_UNSIGNED;
            goto std_op;
        }
        /* if both pointers, then it must be the '-' op */
        if ((t1 & VT_BTYPE) == VT_PTR && 
            (t2 & VT_BTYPE) == VT_PTR) {
            if (op != '-')
                error("cannot use pointers here");
            //            check_pointer_types(vtop - 1, vtop);
            /* XXX: check that types are compatible */
            u = pointed_size(t1);
            gen_opic(op);
            /* set to integer type */
            vtop->t = VT_INT; 
            vpushi(u);
            gen_op(TOK_PDIV);
        } else {
            /* exactly one pointer : must be '+' or '-'. */
            if (op != '-' && op != '+')
                error("cannot use pointers here");
            /* Put pointer as first operand */
            if ((t2 & VT_BTYPE) == VT_PTR) {
                vswap();
                swap(&t1, &t2);
            }
            /* XXX: cast to int ? (long long case) */
            vpushi(pointed_size(vtop[-1].t));
            gen_op('*');
#ifdef CONFIG_TCC_BCHECK
            /* if evaluating constant expression, no code should be
               generated, so no bound check */
            if (do_bounds_check && !const_wanted) {
                /* if bounded pointers, we generate a special code to
                   test bounds */
                if (op == '-') {
                    vpushi(0);
                    vswap();
                    gen_op('-');
                }
                gen_bounded_ptr_add();
            } else
#endif
            {
                gen_opic(op);
            }
            /* put again type if gen_opic() swaped operands */
            vtop->t = t1;
        }
    } else if (is_float(bt1) || is_float(bt2)) {
        /* compute bigger type and do implicit casts */
        if (bt1 == VT_LDOUBLE || bt2 == VT_LDOUBLE) {
            t = VT_LDOUBLE;
        } else if (bt1 == VT_DOUBLE || bt2 == VT_DOUBLE) {
            t = VT_DOUBLE;
        } else {
            t = VT_FLOAT;
        }
        /* floats can only be used for a few operations */
        if (op != '+' && op != '-' && op != '*' && op != '/' &&
            (op < TOK_ULT || op > TOK_GT))
            error("invalid operands for binary operation");
        goto std_op;
    } else if (bt1 == VT_LLONG || bt2 == VT_LLONG) {
        /* cast to biggest op */
        t = VT_LLONG;
        /* convert to unsigned if it does not fit in a long long */
        if ((t1 & (VT_BTYPE | VT_UNSIGNED)) == (VT_LLONG | VT_UNSIGNED) ||
            (t2 & (VT_BTYPE | VT_UNSIGNED)) == (VT_LLONG | VT_UNSIGNED))
            t |= VT_UNSIGNED;
        goto std_op;
    } else {
        /* integer operations */
        t = VT_INT;
        /* convert to unsigned if it does not fit in an integer */
        if ((t1 & (VT_BTYPE | VT_UNSIGNED)) == (VT_INT | VT_UNSIGNED) ||
            (t2 & (VT_BTYPE | VT_UNSIGNED)) == (VT_INT | VT_UNSIGNED))
            t |= VT_UNSIGNED;
    std_op:
        /* XXX: currently, some unsigned operations are explicit, so
           we modify them here */
        if (t & VT_UNSIGNED) {
            if (op == TOK_SAR)
                op = TOK_SHR;
            else if (op == '/')
                op = TOK_UDIV;
            else if (op == '%')
                op = TOK_UMOD;
            else if (op == TOK_LT)
                op = TOK_ULT;
            else if (op == TOK_GT)
                op = TOK_UGT;
            else if (op == TOK_LE)
                op = TOK_ULE;
            else if (op == TOK_GE)
                op = TOK_UGE;
        }
        vswap();
        gen_cast(t);
        vswap();
        /* special case for shifts and long long: we keep the shift as
           an integer */
        if (op == TOK_SHR || op == TOK_SAR || op == TOK_SHL)
            gen_cast(VT_INT);
        else
            gen_cast(t);
        if (is_float(t))
            gen_opif(op);
        else if ((t & VT_BTYPE) == VT_LLONG)
            gen_opl(op);
        else
            gen_opic(op);
        if (op >= TOK_ULT && op <= TOK_GT) {
            /* relationnal op: the result is an int */
            vtop->t = VT_INT;
        } else {
            vtop->t = t;
        }
    }
}

/* generic itof for unsigned long long case */
void gen_cvt_itof1(int t)
{
    GFuncContext gf;

    if ((vtop->t & (VT_BTYPE | VT_UNSIGNED)) == 
        (VT_LLONG | VT_UNSIGNED)) {

        gfunc_start(&gf, FUNC_CDECL);
        gfunc_param(&gf);
        if (t == VT_FLOAT)
            vpush_global_sym(func_old_type, TOK___ulltof);
        else if (t == VT_DOUBLE)
            vpush_global_sym(func_old_type, TOK___ulltod);
        else
            vpush_global_sym(func_old_type, TOK___ulltold);
        gfunc_call(&gf);
        vpushi(0);
        vtop->r = REG_FRET;
    } else {
        gen_cvt_itof(t);
    }
}

/* generic ftoi for unsigned long long case */
void gen_cvt_ftoi1(int t)
{
    GFuncContext gf;
    int st;

    if (t == (VT_LLONG | VT_UNSIGNED)) {
        /* not handled natively */
        gfunc_start(&gf, FUNC_CDECL);
        st = vtop->t & VT_BTYPE;
        gfunc_param(&gf);
        if (st == VT_FLOAT)
            vpush_global_sym(func_old_type, TOK___fixunssfdi);
        else if (st == VT_DOUBLE)
            vpush_global_sym(func_old_type, TOK___fixunsdfdi);
        else
            vpush_global_sym(func_old_type, TOK___fixunsxfdi);
        gfunc_call(&gf);
        vpushi(0);
        vtop->r = REG_IRET;
        vtop->r2 = REG_LRET;
    } else {
        gen_cvt_ftoi(t);
    }
}

/* force char or short cast */
void force_charshort_cast(int t)
{
    int bits, dbt;
    dbt = t & VT_BTYPE;
    /* XXX: add optimization if lvalue : just change type and offset */
    if (dbt == VT_BYTE)
        bits = 8;
    else
        bits = 16;
    if (t & VT_UNSIGNED) {
        vpushi((1 << bits) - 1);
        gen_op('&');
    } else {
        bits = 32 - bits;
        vpushi(bits);
        gen_op(TOK_SHL);
        vpushi(bits);
        gen_op(TOK_SAR);
    }
}

/* cast 'vtop' to 't' type */
void gen_cast(int t)
{
    int sbt, dbt, sf, df, c;

    /* special delayed cast for char/short */
    /* XXX: in some cases (multiple cascaded casts), it may still
       be incorrect */
    if (vtop->r & VT_MUSTCAST) {
        vtop->r &= ~VT_MUSTCAST;
        force_charshort_cast(vtop->t);
    }

    dbt = t & (VT_BTYPE | VT_UNSIGNED);
    sbt = vtop->t & (VT_BTYPE | VT_UNSIGNED);

    if (sbt != dbt) {
        sf = is_float(sbt);
        df = is_float(dbt);
        c = (vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST;
        if (sf && df) {
            /* convert from fp to fp */
            if (c) {
                /* constant case: we can do it now */
                /* XXX: in ISOC, cannot do it if error in convert */
                if (dbt == VT_FLOAT && sbt == VT_DOUBLE) 
                    vtop->c.f = (float)vtop->c.d;
                else if (dbt == VT_FLOAT && sbt == VT_LDOUBLE) 
                    vtop->c.f = (float)vtop->c.ld;
                else if (dbt == VT_DOUBLE && sbt == VT_FLOAT) 
                    vtop->c.d = (double)vtop->c.f;
                else if (dbt == VT_DOUBLE && sbt == VT_LDOUBLE) 
                    vtop->c.d = (double)vtop->c.ld;
                else if (dbt == VT_LDOUBLE && sbt == VT_FLOAT) 
                    vtop->c.ld = (long double)vtop->c.f;
                else if (dbt == VT_LDOUBLE && sbt == VT_DOUBLE) 
                    vtop->c.ld = (long double)vtop->c.d;
            } else {
                /* non constant case: generate code */
                gen_cvt_ftof(dbt);
            }
        } else if (df) {
            /* convert int to fp */
            if (c) {
                switch(sbt) {
                case VT_LLONG | VT_UNSIGNED:
                case VT_LLONG:
                    /* XXX: add const cases for long long */
                    goto do_itof;
                case VT_INT | VT_UNSIGNED:
                    switch(dbt) {
                    case VT_FLOAT: vtop->c.f = (float)vtop->c.ui; break;
                    case VT_DOUBLE: vtop->c.d = (double)vtop->c.ui; break;
                    case VT_LDOUBLE: vtop->c.ld = (long double)vtop->c.ui; break;
                    }
                    break;
                default:
                    switch(dbt) {
                    case VT_FLOAT: vtop->c.f = (float)vtop->c.i; break;
                    case VT_DOUBLE: vtop->c.d = (double)vtop->c.i; break;
                    case VT_LDOUBLE: vtop->c.ld = (long double)vtop->c.i; break;
                    }
                    break;
                }
            } else {
            do_itof:
                gen_cvt_itof1(dbt);
            }
        } else if (sf) {
            /* convert fp to int */
            /* we handle char/short/etc... with generic code */
            if (dbt != (VT_INT | VT_UNSIGNED) &&
                dbt != (VT_LLONG | VT_UNSIGNED) &&
                dbt != VT_LLONG)
                dbt = VT_INT;
            if (c) {
                switch(dbt) {
                case VT_LLONG | VT_UNSIGNED:
                case VT_LLONG:
                    /* XXX: add const cases for long long */
                    goto do_ftoi;
                case VT_INT | VT_UNSIGNED:
                    switch(sbt) {
                    case VT_FLOAT: vtop->c.ui = (unsigned int)vtop->c.d; break;
                    case VT_DOUBLE: vtop->c.ui = (unsigned int)vtop->c.d; break;
                    case VT_LDOUBLE: vtop->c.ui = (unsigned int)vtop->c.d; break;
                    }
                    break;
                default:
                    /* int case */
                    switch(sbt) {
                    case VT_FLOAT: vtop->c.i = (int)vtop->c.d; break;
                    case VT_DOUBLE: vtop->c.i = (int)vtop->c.d; break;
                    case VT_LDOUBLE: vtop->c.i = (int)vtop->c.d; break;
                    }
                    break;
                }
            } else {
            do_ftoi:
                gen_cvt_ftoi1(dbt);
            }
            if (dbt == VT_INT && (t & (VT_BTYPE | VT_UNSIGNED)) != dbt) {
                /* additionnal cast for char/short/bool... */
                vtop->t = dbt;
                gen_cast(t);
            }
        } else if ((dbt & VT_BTYPE) == VT_LLONG) {
            if ((sbt & VT_BTYPE) != VT_LLONG) {
                /* scalar to long long */
                if (c) {
                    if (sbt == (VT_INT | VT_UNSIGNED))
                        vtop->c.ll = vtop->c.ui;
                    else
                        vtop->c.ll = vtop->c.i;
                } else {
                    /* machine independant conversion */
                    gv(RC_INT);
                    /* generate high word */
                    if (sbt == (VT_INT | VT_UNSIGNED)) {
                        vpushi(0);
                        gv(RC_INT);
                    } else {
                        gv_dup();
                        vpushi(31);
                        gen_op(TOK_SAR);
                    }
                    /* patch second register */
                    vtop[-1].r2 = vtop->r;
                    vpop();
                }
            }
        } else if (dbt == VT_BOOL) {
            /* scalar to bool */
            vpushi(0);
            gen_op(TOK_NE);
        } else if ((dbt & VT_BTYPE) == VT_BYTE || 
                   (dbt & VT_BTYPE) == VT_SHORT) {
            force_charshort_cast(t);
        } else if ((dbt & VT_BTYPE) == VT_INT) {
            /* scalar to int */
            if (sbt == VT_LLONG) {
                /* from long long: just take low order word */
                lexpand();
                vpop();
            } 
            /* if lvalue and single word type, nothing to do because
               the lvalue already contains the real type size (see
               VT_LVAL_xxx constants) */
        }
    }
    vtop->t = t;
}

/* return type size. Put alignment at 'a' */
int type_size(int t, int *a)
{
    Sym *s;
    int bt;

    bt = t & VT_BTYPE;
    if (bt == VT_STRUCT) {
        /* struct/union */
        s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT) | SYM_STRUCT);
        *a = 4; /* XXX: cannot store it yet. Doing that is safe */
        return s->c;
    } else if (bt == VT_PTR) {
        if (t & VT_ARRAY) {
            s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT));
            return type_size(s->t, a) * s->c;
        } else {
            *a = PTR_SIZE;
            return PTR_SIZE;
        }
    } else if (bt == VT_LDOUBLE) {
        *a = LDOUBLE_ALIGN;
        return LDOUBLE_SIZE;
    } else if (bt == VT_DOUBLE || bt == VT_LLONG) {
        *a = 8;
        return 8;
    } else if (bt == VT_INT || bt == VT_ENUM || bt == VT_FLOAT) {
        *a = 4;
        return 4;
    } else if (bt == VT_SHORT) {
        *a = 2;
        return 2;
    } else {
        /* char, void, function, _Bool */
        *a = 1;
        return 1;
    }
}

/* return the pointed type of t */
int pointed_type(int t)
{
    Sym *s;
    s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT));
    return s->t | (t & ~VT_TYPE);
}

int mk_pointer(int t)
{
    int p;
    p = anon_sym++;
    sym_push(p, t, 0, -1);
    return VT_PTR | (p << VT_STRUCT_SHIFT) | (t & ~VT_TYPE);
}

int is_compatible_types(int t1, int t2)
{
    Sym *s1, *s2;
    int bt1, bt2;

    t1 &= VT_TYPE;
    t2 &= VT_TYPE;
    bt1 = t1 & VT_BTYPE;
    bt2 = t2 & VT_BTYPE;
    if (bt1 == VT_PTR) {
        t1 = pointed_type(t1);
        /* if function, then convert implicitely to function pointer */
        if (bt2 != VT_FUNC) {
            if (bt2 != VT_PTR)
                return 0;
            t2 = pointed_type(t2);
        }
        /* void matches everything */
        t1 &= VT_TYPE;
        t2 &= VT_TYPE;
        if (t1 == VT_VOID || t2 == VT_VOID)
            return 1;
        return is_compatible_types(t1, t2);
    } else if (bt1 == VT_STRUCT || bt2 == VT_STRUCT) {
        return (t2 == t1);
    } else if (bt1 == VT_FUNC) {
        if (bt2 != VT_FUNC)
            return 0;
        s1 = sym_find(((unsigned)t1 >> VT_STRUCT_SHIFT));
        s2 = sym_find(((unsigned)t2 >> VT_STRUCT_SHIFT));
        if (!is_compatible_types(s1->t, s2->t))
            return 0;
        /* XXX: not complete */
        if (s1->c == FUNC_OLD || s2->c == FUNC_OLD)
            return 1;
        if (s1->c != s2->c)
            return 0;
        while (s1 != NULL) {
            if (s2 == NULL)
                return 0;
            if (!is_compatible_types(s1->t, s2->t))
                return 0;
            s1 = s1->next;
            s2 = s2->next;
        }
        if (s2)
            return 0;
        return 1;
    } else {
        /* XXX: not complete */
        return 1;
    }
}

/* print a type. If 'varstr' is not NULL, then the variable is also
   printed in the type */
/* XXX: union */
/* XXX: add array and function pointers */
void type_to_str(char *buf, int buf_size, 
                 int t, const char *varstr)
{
    int bt, v;
    Sym *s, *sa;
    char buf1[256];
    const char *tstr;

    t = t & VT_TYPE;
    bt = t & VT_BTYPE;
    buf[0] = '\0';
    if (t & VT_UNSIGNED)
        pstrcat(buf, buf_size, "unsigned ");
    switch(bt) {
    case VT_VOID:
        tstr = "void";
        goto add_tstr;
    case VT_BOOL:
        tstr = "_Bool";
        goto add_tstr;
    case VT_BYTE:
        tstr = "char";
        goto add_tstr;
    case VT_SHORT:
        tstr = "short";
        goto add_tstr;
    case VT_INT:
        tstr = "int";
        goto add_tstr;
    case VT_LONG:
        tstr = "long";
        goto add_tstr;
    case VT_LLONG:
        tstr = "long long";
        goto add_tstr;
    case VT_FLOAT:
        tstr = "float";
        goto add_tstr;
    case VT_DOUBLE:
        tstr = "double";
        goto add_tstr;
    case VT_LDOUBLE:
        tstr = "long double";
    add_tstr:
        pstrcat(buf, buf_size, tstr);
        break;
    case VT_ENUM:
    case VT_STRUCT:
        if (bt == VT_STRUCT)
            tstr = "struct ";
        else
            tstr = "enum ";
        pstrcat(buf, buf_size, tstr);
        v = (unsigned)t >> VT_STRUCT_SHIFT;
        if (v >= SYM_FIRST_ANOM)
            pstrcat(buf, buf_size, "<anonymous>");
        else
            pstrcat(buf, buf_size, get_tok_str(v, NULL));
        break;
    case VT_FUNC:
        s = sym_find((unsigned)t >> VT_STRUCT_SHIFT);
        type_to_str(buf, buf_size, s->t, varstr);
        pstrcat(buf, buf_size, "(");
        sa = s->next;
        while (sa != NULL) {
            type_to_str(buf1, sizeof(buf1), sa->t, NULL);
            pstrcat(buf, buf_size, buf1);
            sa = sa->next;
            if (sa)
                pstrcat(buf, buf_size, ", ");
        }
        pstrcat(buf, buf_size, ")");
        goto no_var;
    case VT_PTR:
        s = sym_find((unsigned)t >> VT_STRUCT_SHIFT);
        pstrcpy(buf1, sizeof(buf1), "*");
        if (varstr)
            pstrcat(buf1, sizeof(buf1), varstr);
        type_to_str(buf, buf_size, s->t, buf1);
        goto no_var;
    }
    if (varstr) {
        pstrcat(buf, buf_size, " ");
        pstrcat(buf, buf_size, varstr);
    }
 no_var: ;
}

/* verify type compatibility to store vtop in 'dt' type, and generate
   casts if needed. */
void gen_assign_cast(int dt)
{
    int st;
    char buf1[256], buf2[256];

    st = vtop->t; /* source type */
    if ((dt & VT_BTYPE) == VT_PTR) {
        /* special cases for pointers */
        /* a function is implicitely a function pointer */
        if ((st & VT_BTYPE) == VT_FUNC) {
            if (!is_compatible_types(pointed_type(dt), st))
                goto error;
            else
                goto type_ok;
        }
        /* '0' can also be a pointer */
        if ((st & VT_BTYPE) == VT_INT &&
            ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST) &&
            vtop->c.i == 0)
            goto type_ok;
    }
    if (!is_compatible_types(dt, st)) {
    error:
        type_to_str(buf1, sizeof(buf1), st, NULL);
        type_to_str(buf2, sizeof(buf2), dt, NULL);
        error("cannot cast '%s' to '%s'", buf1, buf2);
    }
 type_ok:
    gen_cast(dt);
}

/* store vtop in lvalue pushed on stack */
void vstore(void)
{
    int sbt, dbt, ft, r, t, size, align, bit_size, bit_pos, rc, delayed_cast;
    GFuncContext gf;

    ft = vtop[-1].t;
    sbt = vtop->t & VT_BTYPE;
    dbt = ft & VT_BTYPE;
    if (((sbt == VT_INT || sbt == VT_SHORT) && dbt == VT_BYTE) ||
        (sbt == VT_INT && dbt == VT_SHORT)) {
        /* optimize char/short casts */
        delayed_cast = VT_MUSTCAST;
        vtop->t = ft & VT_TYPE;
    } else {
        delayed_cast = 0;
        gen_assign_cast(ft & VT_TYPE);
    }

    if (sbt == VT_STRUCT) {
        /* if structure, only generate pointer */
        /* structure assignment : generate memcpy */
        /* XXX: optimize if small size */
        vdup();
        gfunc_start(&gf, FUNC_CDECL);
        /* type size */
        size = type_size(vtop->t, &align);
        vpushi(size);
        gfunc_param(&gf);
        /* source */
        vtop->t = VT_INT;
        gaddrof();
        gfunc_param(&gf);
        /* destination */
        vswap();
        vtop->t = VT_INT;
        gaddrof();
        gfunc_param(&gf);

        save_regs(0);
        vpush_global_sym(func_old_type, TOK_memcpy);
        gfunc_call(&gf);
        /* leave source on stack */
    } else if (ft & VT_BITFIELD) {
        /* bitfield store handling */
        bit_pos = (ft >> VT_STRUCT_SHIFT) & 0x3f;
        bit_size = (ft >> (VT_STRUCT_SHIFT + 6)) & 0x3f;
        /* remove bit field info to avoid loops */
        vtop[-1].t = ft & ~(VT_BITFIELD | (-1 << VT_STRUCT_SHIFT));

        /* duplicate destination */
        vdup();
        vtop[-1] = vtop[-2];

        /* mask and shift source */
        vpushi((1 << bit_size) - 1);
        gen_op('&');
        vpushi(bit_pos);
        gen_op(TOK_SHL);
        /* load destination, mask and or with source */
        vswap();
        vpushi(~(((1 << bit_size) - 1) << bit_pos));
        gen_op('&');
        gen_op('|');
        /* store result */
        vstore();
    } else {
#ifdef CONFIG_TCC_BCHECK
        /* bound check case */
        if (vtop[-1].r & VT_MUSTBOUND) {
            vswap();
            gbound();
            vswap();
        }
#endif
        rc = RC_INT;
        if (is_float(ft))
            rc = RC_FLOAT;
        r = gv(rc);  /* generate value */
        /* if lvalue was saved on stack, must read it */
        if ((vtop[-1].r & VT_VALMASK) == VT_LLOCAL) {
            SValue sv;
            t = get_reg(RC_INT);
            sv.t = VT_INT;
            sv.r = VT_LOCAL | VT_LVAL;
            sv.c.ul = vtop[-1].c.ul;
            load(t, &sv);
            vtop[-1].r = t | VT_LVAL;
        }
        store(r, vtop - 1);
        /* two word case handling : store second register at word + 4 */
        if ((ft & VT_BTYPE) == VT_LLONG) {
            vswap();
            /* convert to int to increment easily */
            vtop->t = VT_INT;
            gaddrof();
            vpushi(4);
            gen_op('+');
            vtop->r |= VT_LVAL;
            vswap();
            /* XXX: it works because r2 is spilled last ! */
            store(vtop->r2, vtop - 1);
        }
        vswap();
        vtop--; /* NOT vpop() because on x86 it would flush the fp stack */
        vtop->r |= delayed_cast;
    }
}

/* post defines POST/PRE add. c is the token ++ or -- */
void inc(int post, int c)
{
    test_lvalue();
    vdup(); /* save lvalue */
    if (post) {
        gv_dup(); /* duplicate value */
        vrotb(3);
        vrotb(3);
    }
    /* add constant */
    vpushi(c - TOK_MID); 
    gen_op('+');
    vstore(); /* store value */
    if (post)
        vpop(); /* if post op, return saved value */
}

/* Parse GNUC __attribute__ extension. Currently, the following
   extensions are recognized:
   - aligned(n) : set data/function alignment.
   - section(x) : generate data/code in this section.
   - unused : currently ignored, but may be used someday.
 */
void parse_attribute(AttributeDef *ad)
{
    int t, n;

    next();
    skip('(');
    skip('(');
    while (tok != ')') {
        if (tok < TOK_IDENT)
            expect("attribute name");
        t = tok;
        next();
        switch(t) {
        case TOK_SECTION:
        case TOK___SECTION__:
            skip('(');
            if (tok != TOK_STR)
                expect("section name");
            ad->section = find_section((char *)tokc.cstr->data);
            next();
            skip(')');
            break;
        case TOK_ALIGNED:
        case TOK___ALIGNED__:
            skip('(');
            n = expr_const();
            if (n <= 0 || (n & (n - 1)) != 0) 
                error("alignment must be a positive power of two");
            ad->aligned = n;
            skip(')');
            break;
        case TOK_UNUSED:
        case TOK___UNUSED__:
            /* currently, no need to handle it because tcc does not
               track unused objects */
            break;
        case TOK_NORETURN:
        case TOK___NORETURN__:
            /* currently, no need to handle it because tcc does not
               track unused objects */
            break;
        case TOK_CDECL:
        case TOK___CDECL:
        case TOK___CDECL__:
            ad->func_call = FUNC_CDECL;
            break;
        case TOK_STDCALL:
        case TOK___STDCALL:
        case TOK___STDCALL__:
            ad->func_call = FUNC_STDCALL;
            break;
        default:
            warning("'%s' attribute ignored", get_tok_str(t, NULL));
            /* skip parameters */
            /* XXX: skip parenthesis too */
            if (tok == '(') {
                next();
                while (tok != ')' && tok != -1)
                    next();
                next();
            }
            break;
        }
        if (tok != ',')
            break;
        next();
    }
    skip(')');
    skip(')');
}

/* enum/struct/union declaration */
int struct_decl(int u)
{
    int a, t, b, v, size, align, maxalign, c, offset;
    int bit_size, bit_pos, bsize, bt, lbit_pos;
    Sym *s, *ss, **ps;
    AttributeDef ad;

    a = tok; /* save decl type */
    next();
    if (tok != '{') {
        v = tok;
        next();
        /* struct already defined ? return it */
        /* XXX: check consistency */
        s = sym_find(v | SYM_STRUCT);
        if (s) {
            if (s->t != a)
                error("invalid type");
            goto do_decl;
        }
    } else {
        v = anon_sym++;
    }
    s = sym_push(v | SYM_STRUCT, a, 0, 0);
    /* put struct/union/enum name in type */
 do_decl:
    u = u | (v << VT_STRUCT_SHIFT);
    
    if (tok == '{') {
        next();
        if (s->c)
            error("struct/union/enum already defined");
        /* cannot be empty */
        c = 0;
        maxalign = 0;
        ps = &s->next;
        bit_pos = 0;
        offset = 0;
        while (1) {
            if (a == TOK_ENUM) {
                v = tok;
                next();
                if (tok == '=') {
                    next();
                    c = expr_const();
                }
                /* enum symbols have static storage */
                sym_push(v, VT_STATIC | VT_INT, VT_CONST, c);
                if (tok == ',')
                    next();
                c++;
            } else {
                parse_btype(&b, &ad);
                while (1) {
                    bit_size = -1;
                    v = 0;
                    if (tok != ':') {
                        t = type_decl(&ad, &v, b, TYPE_DIRECT);
                        if ((t & VT_BTYPE) == VT_FUNC ||
                            (t & (VT_TYPEDEF | VT_STATIC | VT_EXTERN)))
                            error("invalid type for '%s'", 
                                  get_tok_str(v, NULL));
                    } else {
                        t = b;
                    }
                    if (tok == ':') {
                        next();
                        bit_size = expr_const();
                        /* XXX: handle v = 0 case for messages */
                        if (bit_size < 0)
                            error("negative width in bit-field '%s'", 
                                  get_tok_str(v, NULL));
                        if (v && bit_size == 0)
                            error("zero width for bit-field '%s'", 
                                  get_tok_str(v, NULL));
                    }
                    size = type_size(t, &align);
                    lbit_pos = 0;
                    if (bit_size >= 0) {
                        bt = t & VT_BTYPE;
                        if (bt != VT_INT && 
                            bt != VT_BYTE && 
                            bt != VT_SHORT)
                            error("bitfields must have scalar type");
                        bsize = size * 8;
                        if (bit_size > bsize) {
                            error("width of '%s' exceeds its type",
                                  get_tok_str(v, NULL));
                        } else if (bit_size == bsize) {
                            /* no need for bit fields */
                            bit_pos = 0;
                        } else if (bit_size == 0) {
                            /* XXX: what to do if only padding in a
                               structure ? */
                            /* zero size: means to pad */
                            if (bit_pos > 0)
                                bit_pos = bsize;
                        } else {
                            /* we do not have enough room ? */
                            if ((bit_pos + bit_size) > bsize)
                                bit_pos = 0;
                            lbit_pos = bit_pos;
                            /* XXX: handle LSB first */
                            t |= VT_BITFIELD | 
                                (bit_pos << VT_STRUCT_SHIFT) |
                                (bit_size << (VT_STRUCT_SHIFT + 6));
                            bit_pos += bit_size;
                        }
                    } else {
                        bit_pos = 0;
                    }
                    if (v) {
                        /* add new memory data only if starting
                           bit field */
                        if (lbit_pos == 0) {
                            if (a == TOK_STRUCT) {
                                c = (c + align - 1) & -align;
                                offset = c;
                                c += size;
                            } else {
                                offset = 0;
                                if (size > c)
                                    c = size;
                            }
                            if (align > maxalign)
                                maxalign = align;
                        }
#if 0
                        printf("add field %s offset=%d", 
                               get_tok_str(v, NULL), offset);
                        if (t & VT_BITFIELD) {
                            printf(" pos=%d size=%d", 
                                   (t >> VT_STRUCT_SHIFT) & 0x3f,
                                   (t >> (VT_STRUCT_SHIFT + 6)) & 0x3f);
                        }
                        printf("\n");
#endif
                        ss = sym_push(v | SYM_FIELD, t, 0, offset);
                        *ps = ss;
                        ps = &ss->next;
                    }
                    if (tok == ';' || tok == -1)
                        break;
                    skip(',');
                }
                skip(';');
            }
            if (tok == '}')
                break;
        }
        skip('}');
        /* size for struct/union, dummy for enum */
        s->c = (c + maxalign - 1) & -maxalign; 
    }
    return u;
}

/* return 0 if no type declaration. otherwise, return the basic type
   and skip it. 
 */
int parse_btype(int *type_ptr, AttributeDef *ad)
{
    int t, u, type_found;
    Sym *s;

    memset(ad, 0, sizeof(AttributeDef));
    type_found = 0;
    t = 0;
    while(1) {
        switch(tok) {
            /* basic types */
        case TOK_CHAR:
            u = VT_BYTE;
        basic_type:
            next();
        basic_type1:
            if ((t & VT_BTYPE) != 0)
                error("too many basic types");
            t |= u;
            break;
        case TOK_VOID:
            u = VT_VOID;
            goto basic_type;
        case TOK_SHORT:
            u = VT_SHORT;
            goto basic_type;
        case TOK_INT:
            next();
            break;
        case TOK_LONG:
            next();
            if ((t & VT_BTYPE) == VT_DOUBLE) {
                t = (t & ~VT_BTYPE) | VT_LDOUBLE;
            } else if ((t & VT_BTYPE) == VT_LONG) {
                t = (t & ~VT_BTYPE) | VT_LLONG;
            } else {
                u = VT_LONG;
                goto basic_type1;
            }
            break;
        case TOK_BOOL:
            u = VT_BOOL;
            goto basic_type;
        case TOK_FLOAT:
            u = VT_FLOAT;
            goto basic_type;
        case TOK_DOUBLE:
            next();
            if ((t & VT_BTYPE) == VT_LONG) {
                t = (t & ~VT_BTYPE) | VT_LDOUBLE;
            } else {
                u = VT_DOUBLE;
                goto basic_type1;
            }
            break;
        case TOK_ENUM:
            u = struct_decl(VT_ENUM);
            goto basic_type1;
        case TOK_STRUCT:
        case TOK_UNION:
            u = struct_decl(VT_STRUCT);
            goto basic_type1;

            /* type modifiers */
        case TOK_CONST:
        case TOK_VOLATILE:
        case TOK_REGISTER:
        case TOK_SIGNED:
        case TOK___SIGNED__:
        case TOK_AUTO:
        case TOK_INLINE:
        case TOK___INLINE__:
        case TOK_RESTRICT:
            next();
            break;
        case TOK_UNSIGNED:
            t |= VT_UNSIGNED;
            next();
            break;

            /* storage */
        case TOK_EXTERN:
            t |= VT_EXTERN;
            next();
            break;
        case TOK_STATIC:
            t |= VT_STATIC;
            next();
            break;
        case TOK_TYPEDEF:
            t |= VT_TYPEDEF;
            next();
            break;
            /* GNUC attribute */
        case TOK___ATTRIBUTE__:
            parse_attribute(ad);
            break;
        default:
            s = sym_find(tok);
            if (!s || !(s->t & VT_TYPEDEF))
                goto the_end;
            t |= (s->t & ~VT_TYPEDEF);
            next();
            break;
        }
        type_found = 1;
    }
the_end:
    /* long is never used as type */
    if ((t & VT_BTYPE) == VT_LONG)
        t = (t & ~VT_BTYPE) | VT_INT;
    *type_ptr = t;
    return type_found;
}

int post_type(int t, AttributeDef *ad)
{
    int p, n, pt, l, t1;
    Sym **plast, *s, *first;
    AttributeDef ad1;

    if (tok == '(') {
        /* function declaration */
        next();
        l = 0;
        first = NULL;
        plast = &first;
        while (tok != ')') {
            /* read param name and compute offset */
            if (l != FUNC_OLD) {
                if (!parse_btype(&pt, &ad1)) {
                    if (l) {
                        error("invalid type");
                    } else {
                        l = FUNC_OLD;
                        goto old_proto;
                    }
                }
                l = FUNC_NEW;
                if ((pt & VT_BTYPE) == VT_VOID && tok == ')')
                    break;
                pt = type_decl(&ad1, &n, pt, TYPE_DIRECT | TYPE_ABSTRACT);
                if ((pt & VT_BTYPE) == VT_VOID)
                    error("parameter declared as void");
            } else {
            old_proto:
                n = tok;
                pt = VT_INT;
                next();
            }
            /* array must be transformed to pointer according to ANSI C */
            pt &= ~VT_ARRAY;
            s = sym_push(n | SYM_FIELD, pt, 0, 0);
            *plast = s;
            plast = &s->next;
            if (tok == ',') {
                next();
                if (l == FUNC_NEW && tok == TOK_DOTS) {
                    l = FUNC_ELLIPSIS;
                    next();
                    break;
                }
            }
        }
        /* if no parameters, then old type prototype */
        if (l == 0)
            l = FUNC_OLD;
        skip(')');
        t1 = t & (VT_TYPEDEF | VT_STATIC | VT_EXTERN);
        t = post_type(t & ~(VT_TYPEDEF | VT_STATIC | VT_EXTERN), ad);
        /* we push a anonymous symbol which will contain the function prototype */
        p = anon_sym++;
        s = sym_push(p, t, ad->func_call, l);
        s->next = first;
        t = t1 | VT_FUNC | (p << VT_STRUCT_SHIFT);
    } else if (tok == '[') {
        /* array definition */
        next();
        n = -1;
        if (tok != ']') {
            n = expr_const();
            if (n < 0)
                error("invalid array size");    
        }
        skip(']');
        /* parse next post type */
        t1 = t & (VT_TYPEDEF | VT_STATIC | VT_EXTERN);
        t = post_type(t & ~(VT_TYPEDEF | VT_STATIC | VT_EXTERN), ad);
        
        /* we push a anonymous symbol which will contain the array
           element type */
        p = anon_sym++;
        sym_push(p, t, 0, n);
        t = t1 | VT_ARRAY | VT_PTR | (p << VT_STRUCT_SHIFT);
    }
    return t;
}

/* Read a type declaration (except basic type), and return the
   type. 'td' is a bitmask indicating which kind of type decl is
   expected. 't' should contain the basic type. 'ad' is the attribute
   definition of the basic type. It can be modified by type_decl(). */
int type_decl(AttributeDef *ad, int *v, int t, int td)
{
    int u, p;
    Sym *s;

    while (tok == '*') {
        next();
        while (tok == TOK_CONST || tok == TOK_VOLATILE || tok == TOK_RESTRICT)
            next();
        t = mk_pointer(t);
    }
    
    /* recursive type */
    /* XXX: incorrect if abstract type for functions (e.g. 'int ()') */
    if (tok == '(') {
        next();
        /* XXX: this is not correct to modify 'ad' at this point, but
           the syntax is not clear */
        if (tok == TOK___ATTRIBUTE__)
            parse_attribute(ad);
        u = type_decl(ad, v, 0, td);
        skip(')');
    } else {
        u = 0;
        /* type identifier */
        if (tok >= TOK_IDENT && (td & TYPE_DIRECT)) {
            *v = tok;
            next();
        } else {
            if (!(td & TYPE_ABSTRACT))
                expect("identifier");
            *v = 0;
        }
    }
    /* append t at the end of u */
    t = post_type(t, ad);
    if (tok == TOK___ATTRIBUTE__)
        parse_attribute(ad);
    if (!u)
        return t;
    p = u;
    while(1) {
        s = sym_find((unsigned)p >> VT_STRUCT_SHIFT);
        p = s->t;
        if (!p) {
            s->t = t;
            break;
        }
    }
    return u;
}

/* compute the lvalue VT_LVAL_xxx needed to match type t. */
static int lvalue_type(int t)
{
    int bt, r;
    r = VT_LVAL;
    bt = t & VT_BTYPE;
    if (bt == VT_BYTE)
        r |= VT_LVAL_BYTE;
    else if (bt == VT_SHORT)
        r |= VT_LVAL_SHORT;
    else
        return r;
    if (t & VT_UNSIGNED)
        r |= VT_LVAL_UNSIGNED;
    return r;
}

/* indirection with full error checking and bound check */
static void indir(void)
{
    if ((vtop->t & VT_BTYPE) != VT_PTR)
        expect("pointer");
    if (vtop->r & VT_LVAL)
        gv(RC_INT);
    vtop->t = pointed_type(vtop->t);
    /* an array is never an lvalue */
    if (!(vtop->t & VT_ARRAY)) {
        vtop->r |= lvalue_type(vtop->t);
        /* if bound checking, the referenced pointer must be checked */
        if (do_bounds_check) 
            vtop->r |= VT_MUSTBOUND;
    }
}

/* pass a parameter to a function and do type checking and casting */
void gfunc_param_typed(GFuncContext *gf, Sym *func, Sym *arg)
{
    int func_type;
    func_type = func->c;
    if (func_type == FUNC_OLD ||
        (func_type == FUNC_ELLIPSIS && arg == NULL)) {
        /* default casting : only need to convert float to double */
        if ((vtop->t & VT_BTYPE) == VT_FLOAT)
            gen_cast(VT_DOUBLE);
    } else if (arg == NULL) {
        error("too many arguments to function");
    } else {
        gen_assign_cast(arg->t);
    }
    gfunc_param(gf);
}

void unary(void)
{
    int n, t, ft, align, size, r;
    Sym *s;
    GFuncContext gf;
    AttributeDef ad;

    if (tok == TOK_CINT || tok == TOK_CCHAR || tok == TOK_LCHAR) {
        vpushi(tokc.i);
        next();
    } else if (tok == TOK_CUINT) {
        vsetc(VT_INT | VT_UNSIGNED, VT_CONST, &tokc);
        next();
    } else if (tok == TOK_CLLONG) {
        vsetc(VT_LLONG, VT_CONST, &tokc);
        next();
    } else if (tok == TOK_CULLONG) {
        vsetc(VT_LLONG | VT_UNSIGNED, VT_CONST, &tokc);
        next();
    } else if (tok == TOK_CFLOAT) {
        vsetc(VT_FLOAT, VT_CONST, &tokc);
        next();
    } else if (tok == TOK_CDOUBLE) {
        vsetc(VT_DOUBLE, VT_CONST, &tokc);
        next();
    } else if (tok == TOK_CLDOUBLE) {
        vsetc(VT_LDOUBLE, VT_CONST, &tokc);
        next();
    } else if (tok == TOK___FUNC__) {
        void *ptr;
        int len;
        /* special function name identifier */

        len = strlen(funcname) + 1;
        /* generate char[len] type */
        t = VT_ARRAY | mk_pointer(VT_BYTE);
        s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT));
        s->c = len;
        vpush_ref(t, data_section, data_section->data_offset, len);
        ptr = section_ptr_add(data_section, len);
        memcpy(ptr, funcname, len);
        next();
    } else if (tok == TOK_LSTR) {
        t = VT_INT;
        goto str_init;
    } else if (tok == TOK_STR) {
        /* string parsing */
        t = VT_BYTE;
    str_init:
        t = VT_ARRAY | mk_pointer(t);
        memset(&ad, 0, sizeof(AttributeDef));
        decl_initializer_alloc(t, &ad, VT_CONST, 2, 0, 0);
    } else {
        t = tok;
        next();
        if (t == '(') {
            /* cast ? */
            if (parse_btype(&t, &ad)) {
                ft = type_decl(&ad, &n, t, TYPE_ABSTRACT);
                skip(')');
                /* check ISOC99 compound literal */
                if (tok == '{') {
                    /* data is allocated locally by default */
                    if (global_expr)
                        r = VT_CONST;
                    else
                        r = VT_LOCAL;
                    /* all except arrays are lvalues */
                    if (!(ft & VT_ARRAY))
                        r |= lvalue_type(ft);
                    memset(&ad, 0, sizeof(AttributeDef));
                    decl_initializer_alloc(ft, &ad, r, 1, 0, 0);
                } else {
                    unary();
                    gen_cast(ft);
                }
            } else {
                gexpr();
                skip(')');
            }
        } else if (t == '*') {
            unary();
            indir();
        } else if (t == '&') {
            unary();
            /* functions names must be treated as function pointers,
               except for unary '&' and sizeof. Since we consider that
               functions are not lvalues, we only have to handle it
               there and in function calls. */
            /* arrays can also be used although they are not lvalues */
            if ((vtop->t & VT_BTYPE) != VT_FUNC &&
                !(vtop->t & VT_ARRAY))
                test_lvalue();
            vtop->t = mk_pointer(vtop->t);
            gaddrof();
        } else
        if (t == '!') {
            unary();
            if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) == VT_CONST)
                vtop->c.i = !vtop->c.i;
            else if ((vtop->r & VT_VALMASK) == VT_CMP)
                vtop->c.i = vtop->c.i ^ 1;
            else
                vset(VT_INT, VT_JMP, gtst(1, 0));
        } else
        if (t == '~') {
            unary();
            vpushi(-1);
            gen_op('^');
        } else 
        if (t == '+') {
            /* in order to force cast, we add zero */
            unary();
            if ((vtop->t & VT_BTYPE) == VT_PTR)
                error("pointer not accepted for unary plus");
            vpushi(0);
            gen_op('+');
        } else 
        if (t == TOK_SIZEOF) {
            if (tok == '(') {
                next();
                if (parse_btype(&t, &ad)) {
                    t = type_decl(&ad, &n, t, TYPE_ABSTRACT);
                } else {
                    /* XXX: some code could be generated: add eval
                       flag */
                    gexpr();
                    t = vtop->t;
                    vpop();
                }
                skip(')');
            } else {
                unary();
                t = vtop->t;
                vpop();
            }
            vpushi(type_size(t, &t));
        } else
        if (t == TOK_INC || t == TOK_DEC) {
            unary();
            inc(0, t);
        } else if (t == '-') {
            vpushi(0);
            unary();
            gen_op('-');
        } else 
        {
            if (t < TOK_UIDENT)
                expect("identifier");
            s = sym_find(t);
            if (!s) {
                if (tok != '(')
                    error("'%s' undeclared", get_tok_str(t, NULL));
                /* for simple function calls, we tolerate undeclared
                   external reference to int() function */
                s = external_global_sym(t, func_old_type, 0); 
            }
            vset(s->t, s->r, s->c);
            /* if forward reference, we must point to s */
            if (vtop->r & VT_SYM) {
                vtop->sym = s;
                vtop->c.ul = 0;
            }
        }
    }
    
    /* post operations */
    while (1) {
        if (tok == TOK_INC || tok == TOK_DEC) {
            inc(1, tok);
            next();
        } else if (tok == '.' || tok == TOK_ARROW) {
            /* field */ 
            if (tok == TOK_ARROW) 
                indir();
            test_lvalue();
            gaddrof();
            next();
            /* expect pointer on structure */
            if ((vtop->t & VT_BTYPE) != VT_STRUCT)
                expect("struct or union");
            s = sym_find(((unsigned)vtop->t >> VT_STRUCT_SHIFT) | SYM_STRUCT);
            /* find field */
            tok |= SYM_FIELD;
            while ((s = s->next) != NULL) {
                if (s->v == tok)
                    break;
            }
            if (!s)
                error("field not found");
            /* add field offset to pointer */
            vtop->t = char_pointer_type; /* change type to 'char *' */
            vpushi(s->c);
            gen_op('+');
            /* change type to field type, and set to lvalue */
            vtop->t = s->t;
            /* an array is never an lvalue */
            if (!(vtop->t & VT_ARRAY))
                vtop->r |= lvalue_type(vtop->t);
            next();
        } else if (tok == '[') {
            next();
            gexpr();
            gen_op('+');
            indir();
            skip(']');
        } else if (tok == '(') {
            SValue ret;
            Sym *sa;

            /* function call  */
            if ((vtop->t & VT_BTYPE) != VT_FUNC) {
                /* pointer test (no array accepted) */
                if ((vtop->t & (VT_BTYPE | VT_ARRAY)) == VT_PTR) {
                    vtop->t = pointed_type(vtop->t);
                    if ((vtop->t & VT_BTYPE) != VT_FUNC)
                        goto error_func;
                } else {
                error_func:
                    expect("function pointer");
                }
            } else {
                vtop->r &= ~VT_LVAL; /* no lvalue */
            }
            /* get return type */
            s = sym_find((unsigned)vtop->t >> VT_STRUCT_SHIFT);
            save_regs(0); /* save used temporary registers */
            gfunc_start(&gf, s->r);
            next();
            sa = s->next; /* first parameter */
#ifdef INVERT_FUNC_PARAMS
            {
                int parlevel;
                Sym *args, *s1;
                ParseState saved_parse_state;
                TokenString str;
                
                /* read each argument and store it on a stack */
                /* XXX: merge it with macro args ? */
                args = NULL;
                if (tok != ')') {
                    for(;;) {
                        tok_str_new(&str);
                        parlevel = 0;
                        while ((parlevel > 0 || (tok != ')' && tok != ',')) && 
                               tok != TOK_EOF) {
                            if (tok == '(')
                                parlevel++;
                            else if (tok == ')')
                                parlevel--;
                            tok_str_add_tok(&str);
                            next();
                        }
                        tok_str_add(&str, -1); /* end of file added */
                        tok_str_add(&str, 0);
                        s1 = sym_push2(&args, 0, 0, (int)str.str);
                        s1->next = sa; /* add reference to argument */
                        if (sa)
                            sa = sa->next;
                        if (tok == ')')
                            break;
                        skip(',');
                    }
                }
                
                /* now generate code in reverse order by reading the stack */
                save_parse_state(&saved_parse_state);
                while (args) {
                    macro_ptr = (int *)args->c;
                    next();
                    expr_eq();
                    if (tok != -1)
                        expect("',' or ')'");
                    gfunc_param_typed(&gf, s, args->next);
                    s1 = args->prev;
                    tok_str_free((int *)args->c);
                    tcc_free(args);
                    args = s1;
                }
                restore_parse_state(&saved_parse_state);
            }
#endif
            /* compute first implicit argument if a structure is returned */
            if ((s->t & VT_BTYPE) == VT_STRUCT) {
                /* get some space for the returned structure */
                size = type_size(s->t, &align);
                loc = (loc - size) & -align;
                ret.t = s->t;
                ret.r = VT_LOCAL | VT_LVAL;
                /* pass it as 'int' to avoid structure arg passing
                   problems */
                vset(VT_INT, VT_LOCAL, loc);
                ret.c = vtop->c;
                gfunc_param(&gf);
            } else {
                ret.t = s->t; 
                ret.r2 = VT_CONST;
                /* return in register */
                if (is_float(ret.t)) {
                    ret.r = REG_FRET; 
                } else {
                    if ((ret.t & VT_BTYPE) == VT_LLONG)
                        ret.r2 = REG_LRET;
                    ret.r = REG_IRET;
                }
                ret.c.i = 0;
            }
#ifndef INVERT_FUNC_PARAMS
            if (tok != ')') {
                for(;;) {
                    expr_eq();
                    gfunc_param_typed(&gf, s, sa);
                    if (sa)
                        sa = sa->next;
                    if (tok == ')')
                        break;
                    skip(',');
                }
            }
#endif
            if (sa)
                error("too few arguments to function");
            skip(')');
            gfunc_call(&gf);
            /* return value */
            vsetc(ret.t, ret.r, &ret.c);
            vtop->r2 = ret.r2;
        } else {
            break;
        }
    }
}

void uneq(void)
{
    int t;
    
    unary();
    if (tok == '=' ||
        (tok >= TOK_A_MOD && tok <= TOK_A_DIV) ||
        tok == TOK_A_XOR || tok == TOK_A_OR ||
        tok == TOK_A_SHL || tok == TOK_A_SAR) {
        test_lvalue();
        t = tok;
        next();
        if (t == '=') {
            expr_eq();
        } else {
            vdup();
            expr_eq();
            gen_op(t & 0x7f);
        }
        vstore();
    }
}

void sum(int l)
{
    int t;

    if (l == 0)
        uneq();
    else {
        sum(--l);
        while ((l == 0 && (tok == '*' || tok == '/' || tok == '%')) ||
               (l == 1 && (tok == '+' || tok == '-')) ||
               (l == 2 && (tok == TOK_SHL || tok == TOK_SAR)) ||
               (l == 3 && ((tok >= TOK_ULE && tok <= TOK_GT) ||
                          tok == TOK_ULT || tok == TOK_UGE)) ||
               (l == 4 && (tok == TOK_EQ || tok == TOK_NE)) ||
               (l == 5 && tok == '&') ||
               (l == 6 && tok == '^') ||
               (l == 7 && tok == '|') ||
               (l == 8 && tok == TOK_LAND) ||
               (l == 9 && tok == TOK_LOR)) {
            t = tok;
            next();
            sum(l);
            gen_op(t);
       }
    }
}

/* only used if non constant */
void eand(void)
{
    int t;

    sum(8);
    t = 0;
    while (1) {
        if (tok != TOK_LAND) {
            if (t) {
                t = gtst(1, t);
                vset(VT_INT, VT_JMPI, t);
            }
            break;
        }
        t = gtst(1, t);
        next();
        sum(8);
    }
}

void eor(void)
{
    int t;

    eand();
    t = 0;
    while (1) {
        if (tok != TOK_LOR) {
            if (t) {
                t = gtst(0, t);
                vset(VT_INT, VT_JMP, t);
            }
            break;
        }
        t = gtst(0, t);
        next();
        eand();
    }
}

/* XXX: better constant handling */
void expr_eq(void)
{
    int t, u, c, r1, r2, rc;

    if (const_wanted) {
        sum(10);
        if (tok == '?') {
            c = vtop->c.i;
            vpop();
            next();
            gexpr();
            t = vtop->c.i;
            vpop();
            skip(':');
            expr_eq();
            if (c)
                vtop->c.i = t;
        }
    } else {
        eor();
        if (tok == '?') {
            next();
            save_regs(1); /* we need to save all registers here except
                             at the top because it is a branch point */
            t = gtst(1, 0);
            gexpr();
            /* XXX: long long handling ? */
            rc = RC_INT;
            if (is_float(vtop->t))
                rc = RC_FLOAT;
            r1 = gv(rc);
            vtop--; /* no vpop so that FP stack is not flushed */
            skip(':');
            u = gjmp(0);

            gsym(t);
            expr_eq();
            r2 = gv(rc);
            move_reg(r1, r2);
            vtop->r = r1;
            gsym(u);
        }
    }
}

void gexpr(void)
{
    while (1) {
        expr_eq();
        if (tok != ',')
            break;
        vpop();
        next();
    }
}

/* parse a constant expression and return value in vtop.  */
static void expr_const1(void)
{
    int a;
    a = const_wanted;
    const_wanted = 1;
    expr_eq();
    const_wanted = a;
}

/* parse an integer constant and return its value. */
static int expr_const(void)
{
    int c;
    expr_const1();
    if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_SYM)) != VT_CONST)
        expect("constant expression");
    c = vtop->c.i;
    vpop();
    return c;
}

/* return the label token if current token is a label, otherwise
   return zero */
int is_label(void)
{
    int t;
    CValue c;

    /* fast test first */
    if (tok < TOK_UIDENT)
        return 0;
    /* no need to save tokc since we expect an identifier */
    t = tok;
    c = tokc;
    next();
    if (tok == ':') {
        next();
        return t;
    } else {
        /* XXX: may not work in all cases (macros ?) */
        tok1 = tok;
        tok1c = tokc;
        tok = t;
        tokc = c;
        return 0;
    }
}

void block(int *bsym, int *csym, int *case_sym, int *def_sym, int case_reg)
{
    int a, b, c, d;
    Sym *s;

    /* generate line number info */
    if (do_debug && 
        (last_line_num != file->line_num || last_ind != ind)) {
        put_stabn(N_SLINE, 0, file->line_num, ind - func_ind);
        last_ind = ind;
        last_line_num = file->line_num;
    }

    if (tok == TOK_IF) {
        /* if test */
        next();
        skip('(');
        gexpr();
        skip(')');
        a = gtst(1, 0);
        block(bsym, csym, case_sym, def_sym, case_reg);
        c = tok;
        if (c == TOK_ELSE) {
            next();
            d = gjmp(0);
            gsym(a);
            block(bsym, csym, case_sym, def_sym, case_reg);
            gsym(d); /* patch else jmp */
        } else
            gsym(a);
    } else if (tok == TOK_WHILE) {
        next();
        d = ind;
        skip('(');
        gexpr();
        skip(')');
        a = gtst(1, 0);
        b = 0;
        block(&a, &b, case_sym, def_sym, case_reg);
        gjmp_addr(d);
        gsym(a);
        gsym_addr(b, d);
    } else if (tok == '{') {
        next();
        /* declarations */
        s = local_stack.top;
        while (tok != '}') {
            decl(VT_LOCAL);
            if (tok != '}')
                block(bsym, csym, case_sym, def_sym, case_reg);
        }
        /* pop locally defined symbols */
        sym_pop(&local_stack, s);
        next();
    } else if (tok == TOK_RETURN) {
        next();
        if (tok != ';') {
            gexpr();
            gen_assign_cast(func_vt);
            if ((func_vt & VT_BTYPE) == VT_STRUCT) {
                /* if returning structure, must copy it to implicit
                   first pointer arg location */
                vset(mk_pointer(func_vt), VT_LOCAL | VT_LVAL, func_vc);
                indir();
                vswap();
                /* copy structure value to pointer */
                vstore();
            } else if (is_float(func_vt)) {
                gv(RC_FRET);
            } else {
                gv(RC_IRET);
            }
            vtop--; /* NOT vpop() because on x86 it would flush the fp stack */
        }
        skip(';');
        rsym = gjmp(rsym); /* jmp */
    } else if (tok == TOK_BREAK) {
        /* compute jump */
        if (!bsym)
            error("cannot break");
        *bsym = gjmp(*bsym);
        next();
        skip(';');
    } else if (tok == TOK_CONTINUE) {
        /* compute jump */
        if (!csym)
            error("cannot continue");
        *csym = gjmp(*csym);
        next();
        skip(';');
    } else if (tok == TOK_FOR) {
        int e;
        next();
        skip('(');
        if (tok != ';') {
            gexpr();
            vpop();
        }
        skip(';');
        d = ind;
        c = ind;
        a = 0;
        b = 0;
        if (tok != ';') {
            gexpr();
            a = gtst(1, 0);
        }
        skip(';');
        if (tok != ')') {
            e = gjmp(0);
            c = ind;
            gexpr();
            vpop();
            gjmp_addr(d);
            gsym(e);
        }
        skip(')');
        block(&a, &b, case_sym, def_sym, case_reg);
        gjmp_addr(c);
        gsym(a);
        gsym_addr(b, c);
    } else 
    if (tok == TOK_DO) {
        next();
        a = 0;
        b = 0;
        d = ind;
        block(&a, &b, case_sym, def_sym, case_reg);
        skip(TOK_WHILE);
        skip('(');
        gsym(b);
        gexpr();
        c = gtst(0, 0);
        gsym_addr(c, d);
        skip(')');
        gsym(a);
        skip(';');
    } else
    if (tok == TOK_SWITCH) {
        next();
        skip('(');
        gexpr();
        /* XXX: other types than integer */
        case_reg = gv(RC_INT);
        vpop();
        skip(')');
        a = 0;
        b = gjmp(0); /* jump to first case */
        c = 0;
        block(&a, csym, &b, &c, case_reg);
        /* if no default, jmp after switch */
        if (c == 0)
            c = ind;
        /* default label */
        gsym_addr(b, c);
        /* break label */
        gsym(a);
    } else
    if (tok == TOK_CASE) {
        int v1, v2;
        if (!case_sym)
            expect("switch");
        next();
        v1 = expr_const();
        v2 = v1;
        if (gnu_ext && tok == TOK_DOTS) {
            next();
            v2 = expr_const();
            if (v2 < v1)
                warning("empty case range");
        }
        /* since a case is like a label, we must skip it with a jmp */
        b = gjmp(0);
        gsym(*case_sym);
        vset(VT_INT, case_reg, 0);
        vpushi(v1);
        if (v1 == v2) {
            gen_op(TOK_EQ);
            *case_sym = gtst(1, 0);
        } else {
            gen_op(TOK_GE);
            *case_sym = gtst(1, 0);
            vset(VT_INT, case_reg, 0);
            vpushi(v2);
            gen_op(TOK_LE);
            *case_sym = gtst(1, *case_sym);
        }
        gsym(b);
        skip(':');
        block(bsym, csym, case_sym, def_sym, case_reg);
    } else 
    if (tok == TOK_DEFAULT) {
        next();
        skip(':');
        if (!def_sym)
            expect("switch");
        if (*def_sym)
            error("too many 'default'");
        *def_sym = ind;
        block(bsym, csym, case_sym, def_sym, case_reg);
    } else
    if (tok == TOK_GOTO) {
        next();
        s = sym_find1(&label_stack, tok);
        /* put forward definition if needed */
        if (!s)
            s = sym_push1(&label_stack, tok, LABEL_FORWARD, 0);
        /* label already defined */
        if (s->t & LABEL_FORWARD) 
            s->c = gjmp(s->c);
        else
            gjmp_addr(s->c);
        next();
        skip(';');
    } else {
        b = is_label();
        if (b) {
            /* label case */
            s = sym_find1(&label_stack, b);
            if (s) {
                if (!(s->t & LABEL_FORWARD))
                    error("multiple defined label");
                gsym(s->c);
                s->c = ind;
                s->t = 0;
            } else {
                sym_push1(&label_stack, b, 0, ind);
            }
            /* we accept this, but it is a mistake */
            if (tok == '}') 
                warning("deprecated use of label at end of compound statement");
            else
                block(bsym, csym, case_sym, def_sym, case_reg);
        } else {
            /* expression case */
            if (tok != ';') {
                gexpr();
                vpop();
            }
            skip(';');
        }
    }
}

/* t is the array or struct type. c is the array or struct
   address. cur_index/cur_field is the pointer to the current
   value. 'size_only' is true if only size info is needed (only used
   in arrays) */
static void decl_designator(int t, Section *sec, unsigned long c, 
                            int *cur_index, Sym **cur_field, 
                            int size_only)
{
    Sym *s, *f;
    int notfirst, index, align, l;

    notfirst = 0;
    if (gnu_ext && (l = is_label()) != 0)
        goto struct_field;

    while (tok == '[' || tok == '.') {
        if (tok == '[') {
            if (!(t & VT_ARRAY))
                expect("array type");
            s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT));
            next();
            index = expr_const();
            if (index < 0 || (s->c >= 0 && index >= s->c))
                expect("invalid index");
            skip(']');
            if (!notfirst)
                *cur_index = index;
            t = pointed_type(t);
            c += index * type_size(t, &align);
        } else {
            next();
            l = tok;
            next();
        struct_field:
            if ((t & VT_BTYPE) != VT_STRUCT)
                expect("struct/union type");
            s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT) | SYM_STRUCT);
            l |= SYM_FIELD;
            f = s->next;
            while (f) {
                if (f->v == l)
                    break;
                f = f->next;
            }
            if (!f)
                expect("field");
            if (!notfirst)
                *cur_field = f;
            t = f->t | (t & ~VT_TYPE);
            c += f->c;
        }
        notfirst = 1;
    }
    if (notfirst) {
        if (tok == '=') {
            next();
        } else {
            if (!gnu_ext)
                expect("=");
        }
    } else {
        if (t & VT_ARRAY) {
            index = *cur_index;
            t = pointed_type(t);
            c += index * type_size(t, &align);
        } else {
            f = *cur_field;
            if (!f)
                error("too many field init");
            t = f->t | (t & ~VT_TYPE);
            c += f->c;
        }
    }
    decl_initializer(t, sec, c, 0, size_only);
}

#define EXPR_VAL   0
#define EXPR_CONST 1
#define EXPR_ANY   2

/* store a value or an expression directly in global data or in local array */
static void init_putv(int t, Section *sec, unsigned long c, 
                      int v, int expr_type)
{
    int saved_global_expr, bt;
    void *ptr;

    switch(expr_type) {
    case EXPR_VAL:
        vpushi(v);
        break;
    case EXPR_CONST:
        /* compound literals must be allocated globally in this case */
        saved_global_expr = global_expr;
        global_expr = 1;
        expr_const1();
        global_expr = saved_global_expr;
        /* NOTE: symbols are accepted */
        if ((vtop->r & (VT_VALMASK | VT_LVAL)) != VT_CONST)
            error("initializer element is not constant");
        break;
    case EXPR_ANY:
        expr_eq();
        break;
    }
    
    if (sec) {
        /* XXX: not portable */
        /* XXX: generate error if incorrect relocation */
        gen_assign_cast(t);
        bt = t & VT_BTYPE;
        ptr = sec->data + c;
        if ((vtop->r & VT_SYM) &&
            (bt == VT_BYTE ||
             bt == VT_SHORT ||
             bt == VT_DOUBLE ||
             bt == VT_LDOUBLE ||
             bt == VT_LLONG))
            error("initializer element is not computable at load time");
        switch(bt) {
        case VT_BYTE:
            *(char *)ptr = vtop->c.i;
            break;
        case VT_SHORT:
            *(short *)ptr = vtop->c.i;
            break;
        case VT_DOUBLE:
            *(double *)ptr = vtop->c.d;
            break;
        case VT_LDOUBLE:
            *(long double *)ptr = vtop->c.ld;
            break;
        case VT_LLONG:
            *(long long *)ptr = vtop->c.ll;
            break;
        default:
            if (vtop->r & VT_SYM) {
                greloc(sec, vtop->sym, c, R_DATA_32);
            }
            *(int *)ptr = vtop->c.i;
            break;
        }
        vtop--;
    } else {
        vset(t, VT_LOCAL, c);
        vswap();
        vstore();
        vpop();
    }
}

/* put zeros for variable based init */
static void init_putz(int t, Section *sec, unsigned long c, int size)
{
    GFuncContext gf;

    if (sec) {
        /* nothing to do because globals are already set to zero */
    } else {
        gfunc_start(&gf, FUNC_CDECL);
        vpushi(size);
        gfunc_param(&gf);
        vpushi(0);
        gfunc_param(&gf);
        vset(VT_INT, VT_LOCAL, c);
        gfunc_param(&gf);
        vpush_global_sym(func_old_type, TOK_memset);
        gfunc_call(&gf);
    }
}

/* 't' contains the type and storage info. 'c' is the offset of the
   object in section 'sec'. If 'sec' is NULL, it means stack based
   allocation. 'first' is true if array '{' must be read (multi
   dimension implicit array init handling). 'size_only' is true if
   size only evaluation is wanted (only for arrays). */
static void decl_initializer(int t, Section *sec, unsigned long c, 
                             int first, int size_only)
{
    int index, array_length, n, no_oblock, nb, parlevel, i;
    int t1, size1, align1, expr_type;
    Sym *s, *f;

    if (t & VT_ARRAY) {
        s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT));
        n = s->c;
        array_length = 0;
        t1 = pointed_type(t);
        size1 = type_size(t1, &align1);

        no_oblock = 1;
        if ((first && tok != TOK_LSTR && tok != TOK_STR) || 
            tok == '{') {
            skip('{');
            no_oblock = 0;
        }

        /* only parse strings here if correct type (otherwise: handle
           them as ((w)char *) expressions */
        if ((tok == TOK_LSTR && 
             (t1 & VT_BTYPE) == VT_INT) ||
            (tok == TOK_STR &&
             (t1 & VT_BTYPE) == VT_BYTE)) {
            while (tok == TOK_STR || tok == TOK_LSTR) {
                int cstr_len, ch;
                CString *cstr;

                cstr = tokc.cstr;
                /* compute maximum number of chars wanted */
                if (tok == TOK_STR)
                    cstr_len = cstr->size;
                else
                    cstr_len = cstr->size / sizeof(int);
                cstr_len--;
                nb = cstr_len;
                if (n >= 0 && nb > (n - array_length))
                    nb = n - array_length;
                if (!size_only) {
                    if (cstr_len > nb)
                        warning("initializer-string for array is too long");
                    for(i=0;i<nb;i++) {
                        if (tok == TOK_STR)
                            ch = ((unsigned char *)cstr->data)[i];
                        else
                            ch = ((int *)cstr->data)[i];
                        init_putv(t1, sec, c + (array_length + i) * size1,
                                  ch, EXPR_VAL);
                    }
                }
                array_length += nb;
                next();
            }
            /* only add trailing zero if enough storage (no
               warning in this case since it is standard) */
            if (n < 0 || array_length < n) {
                if (!size_only) {
                    init_putv(t1, sec, c + (array_length * size1), 0, EXPR_VAL);
                }
                array_length++;
            }
        } else {
            index = 0;
            while (tok != '}') {
                decl_designator(t, sec, c, &index, NULL, size_only);
                if (n >= 0 && index >= n)
                    error("index too large");
                /* must put zero in holes (note that doing it that way
                   ensures that it even works with designators) */
                if (!size_only && array_length < index) {
                    init_putz(t1, sec, c + array_length * size1, 
                              (index - array_length) * size1);
                }
                index++;
                if (index > array_length)
                    array_length = index;
                /* special test for multi dimensional arrays (may not
                   be strictly correct if designators are used at the
                   same time) */
                if (index >= n && no_oblock)
                    break;
                if (tok == '}')
                    break;
                skip(',');
            }
        }
        if (!no_oblock)
            skip('}');
        /* put zeros at the end */
        if (!size_only && n >= 0 && array_length < n) {
            init_putz(t1, sec, c + array_length * size1, 
                      (n - array_length) * size1);
        }
        /* patch type size if needed */
        if (n < 0)
            s->c = array_length;
    } else if ((t & VT_BTYPE) == VT_STRUCT && tok == '{') {
        /* XXX: union needs only one init */
        next();
        s = sym_find(((unsigned)t >> VT_STRUCT_SHIFT) | SYM_STRUCT);
        f = s->next;
        array_length = 0;
        index = 0;
        n = s->c;
        while (tok != '}') {
            decl_designator(t, sec, c, NULL, &f, size_only);
            /* fill with zero between fields */
            index = f->c;
            if (!size_only && array_length < index) {
                init_putz(t, sec, c + array_length, 
                          index - array_length);
            }
            index = index + type_size(f->t, &align1);
            if (index > array_length)
                array_length = index;
            if (tok == '}')
                break;
            skip(',');
            f = f->next;
        }
        /* put zeros at the end */
        if (!size_only && array_length < n) {
            init_putz(t, sec, c + array_length, 
                      n - array_length);
        }
        skip('}');
    } else if (tok == '{') {
        next();
        decl_initializer(t, sec, c, first, size_only);
        skip('}');
    } else if (size_only) {
        /* just skip expression */
        parlevel = 0;
        while ((parlevel > 0 || (tok != '}' && tok != ',')) && 
               tok != -1) {
            if (tok == '(')
                parlevel++;
            else if (tok == ')')
                parlevel--;
            next();
        }
    } else {
        /* currently, we always use constant expression for globals
           (may change for scripting case) */
        expr_type = EXPR_CONST;
        if (!sec)
            expr_type = EXPR_ANY;
        init_putv(t, sec, c, 0, expr_type);
    }
}

/* parse an initializer for type 't' if 'has_init' is non zero, and
   allocate space in local or global data space ('r' is either
   VT_LOCAL or VT_CONST). If 'v' is non zero, then an associated
   variable 'v' of scope 'scope' is declared before initializers are
   parsed. If 'v' is zero, then a reference to the new object is put
   in the value stack. If 'has_init' is 2, a special parsing is done
   to handle string constants. */
static void decl_initializer_alloc(int t, AttributeDef *ad, int r, 
                                   int has_init, int v, int scope)
{
    int size, align, addr, data_offset;
    int level;
    ParseState saved_parse_state;
    TokenString init_str;
    Section *sec;

    size = type_size(t, &align);
    /* If unknown size, we must evaluate it before
       evaluating initializers because
       initializers can generate global data too
       (e.g. string pointers or ISOC99 compound
       literals). It also simplifies local
       initializers handling */
    tok_str_new(&init_str);
    if (size < 0) {
        if (!has_init) 
            error("unknown type size");
        /* get all init string */
        if (has_init == 2) {
            /* only get strings */
            while (tok == TOK_STR || tok == TOK_LSTR) {
                tok_str_add_tok(&init_str);
                next();
            }
        } else {
            level = 0;
            while (level > 0 || (tok != ',' && tok != ';')) {
                if (tok < 0)
                    error("unexpected end of file in initializer");
                tok_str_add_tok(&init_str);
                if (tok == '{')
                    level++;
                else if (tok == '}') {
                    if (level == 0)
                        break;
                    level--;
                }
                next();
            }
        }
        tok_str_add(&init_str, -1);
        tok_str_add(&init_str, 0);
        
        /* compute size */
        save_parse_state(&saved_parse_state);

        macro_ptr = init_str.str;
        next();
        decl_initializer(t, NULL, 0, 1, 1);
        /* prepare second initializer parsing */
        macro_ptr = init_str.str;
        next();
        
        /* if still unknown size, error */
        size = type_size(t, &align);
        if (size < 0) 
            error("unknown type size");
    }
    /* take into account specified alignment if bigger */
    if (ad->aligned > align)
        align = ad->aligned;
    if ((r & VT_VALMASK) == VT_LOCAL) {
        sec = NULL;
        if (do_bounds_check && (t & VT_ARRAY)) 
            loc--;
#ifdef TCC_TARGET_IL
        /* XXX: ugly patch to allocate local variables for IL, just
           for testing */
        addr = loc;
        loc++;
#else
        loc = (loc - size) & -align;
        addr = loc;
#endif
        /* handles bounds */
        /* XXX: currently, since we do only one pass, we cannot track
           '&' operators, so we add only arrays */
        if (do_bounds_check && (t & VT_ARRAY)) {
            unsigned long *bounds_ptr;
            /* add padding between regions */
            loc--;
            /* then add local bound info */
            bounds_ptr = section_ptr_add(lbounds_section, 2 * sizeof(unsigned long));
            bounds_ptr[0] = addr;
            bounds_ptr[1] = size;
        }
    } else {
        /* compute section */
        sec = ad->section;
        if (!sec) {
            if (has_init)
                sec = data_section;
            else
                sec = bss_section;
        }
        data_offset = sec->data_offset;
        data_offset = (data_offset + align - 1) & -align;
        addr = data_offset;
        /* very important to increment global pointer at this time
           because initializers themselves can create new initializers */
        data_offset += size;
        /* add padding if bound check */
        if (do_bounds_check)
            data_offset++;
        sec->data_offset = data_offset;
        /* allocate section space to put the data */
        if (sec->sh_type != SHT_NOBITS && 
            data_offset > sec->data_allocated)
            section_realloc(sec, data_offset);
    }
    if (!sec) {
        if (v) {
            /* local variable */
            sym_push(v, t, r, addr);
        } else {
            /* push local reference */
            vset(t, r, addr);
        }
    } else {
        Sym *sym;
        
        if (v) {
            if (scope == VT_CONST) {
                /* global scope: see if already defined */
                sym = sym_find(v);
                if (!sym)
                    goto do_def;
                if (!is_compatible_types(sym->t, t))
                    error("incompatible types for redefinition of '%s'", 
                          get_tok_str(v, NULL));
                if (!(sym->t & VT_EXTERN))
                    error("redefinition of '%s'", get_tok_str(v, NULL));
                sym->t &= ~VT_EXTERN;
            } else {
            do_def:
                sym = sym_push(v, t, r | VT_SYM, 0);
            }
            put_extern_sym(sym, sec, addr, size);
        } else {
            CValue cval;

            /* push global reference */
            sym = get_sym_ref(t, sec, addr, size);
            cval.ul = 0;
            vsetc(t, VT_CONST | VT_SYM, &cval);
            vtop->sym = sym;
        }

        /* handles bounds now because the symbol must be defined
           before for the relocation */
        if (do_bounds_check) {
            unsigned long *bounds_ptr;

            greloc(bounds_section, sym, bounds_section->data_offset, R_DATA_32);
            /* then add global bound info */
            bounds_ptr = section_ptr_add(bounds_section, 2 * sizeof(long));
            bounds_ptr[0] = 0; /* relocated */
            bounds_ptr[1] = size;
        }
    }
    if (has_init) {
        decl_initializer(t, sec, addr, 1, 0);
        /* restore parse state if needed */
        if (init_str.str) {
            tok_str_free(init_str.str);
            restore_parse_state(&saved_parse_state);
        }
    }
}

void put_func_debug(Sym *sym)
{
    char buf[512];

    /* stabs info */
    /* XXX: we put here a dummy type */
    snprintf(buf, sizeof(buf), "%s:%c1", 
             funcname, sym->t & VT_STATIC ? 'f' : 'F');
    put_stabs_r(buf, N_FUN, 0, file->line_num, 0,
                cur_text_section, sym->c);
    last_ind = 0;
    last_line_num = 0;
}

/* not finished : try to put some local vars in registers */
//#define CONFIG_REG_VARS

#ifdef CONFIG_REG_VARS
void add_var_ref(int t)
{
    printf("%s:%d: &%s\n", 
           file->filename, file->line_num,
           get_tok_str(t, NULL));
}

/* first pass on a function with heuristic to extract variable usage
   and pointer references to local variables for register allocation */
void analyse_function(void)
{
    int level, t;

    for(;;) {
        if (tok == -1)
            break;
        /* any symbol coming after '&' is considered as being a
           variable whose reference is taken. It is highly unaccurate
           but it is difficult to do better without a complete parse */
        if (tok == '&') {
            next();
            /* if '& number', then no need to examine next tokens */
            if (tok == TOK_CINT ||
                tok == TOK_CUINT ||
                tok == TOK_CLLONG ||
                tok == TOK_CULLONG) {
                continue;
            } else if (tok >= TOK_UIDENT) {
                /* if '& ident [' or '& ident ->', then ident address
                   is not needed */
                t = tok;
                next();
                if (tok != '[' && tok != TOK_ARROW)
                    add_var_ref(t);
            } else {
                level = 0;
                while (tok != '}' && tok != ';' && 
                       !((tok == ',' || tok == ')') && level == 0)) {
                    if (tok >= TOK_UIDENT) {
                        add_var_ref(tok);
                    } else if (tok == '(') {
                        level++;
                    } else if (tok == ')') {
                        level--;
                    }
                    next();
                }
            }
        } else {
            next();
        }
    }
}
#endif

/* 'l' is VT_LOCAL or VT_CONST to define default storage type */
void decl(int l)
{
    int t, b, v, has_init, r;
    Sym *sym;
    AttributeDef ad;
    
    while (1) {
        if (!parse_btype(&b, &ad)) {
            /* skip redundant ';' */
            /* XXX: find more elegant solution */
            if (tok == ';') {
                next();
                continue;
            }
            /* special test for old K&R protos without explicit int
               type. Only accepted when defining global data */
            if (l == VT_LOCAL || tok < TOK_DEFINE)
                break;
            b = VT_INT;
        }
        if (((b & VT_BTYPE) == VT_ENUM ||
             (b & VT_BTYPE) == VT_STRUCT) && 
            tok == ';') {
            /* we accept no variable after */
            next();
            continue;
        }
        while (1) { /* iterate thru each declaration */
            t = type_decl(&ad, &v, b, TYPE_DIRECT);
#if 0
            {
                char buf[500];
                type_to_str(buf, sizeof(buf), t, get_tok_str(v, NULL));
                printf("type = '%s'\n", buf);
            }
#endif
            if (tok == '{') {
#ifdef CONFIG_REG_VARS
                TokenString func_str;
                ParseState saved_parse_state;
                int block_level;
#endif

                if (l == VT_LOCAL)
                    error("cannot use local functions");
                if (!(t & VT_FUNC))
                    expect("function definition");

#ifdef CONFIG_REG_VARS
                /* parse all function code and record it */

                tok_str_new(&func_str);
                
                block_level = 0;
                for(;;) {
                    int t;
                    if (tok == -1)
                        error("unexpected end of file");
                    tok_str_add_tok(&func_str);
                    t = tok;
                    next();
                    if (t == '{') {
                        block_level++;
                    } else if (t == '}') {
                        block_level--;
                        if (block_level == 0)
                            break;
                    }
                }
                tok_str_add(&func_str, -1);
                tok_str_add(&func_str, 0);

                save_parse_state(&saved_parse_state);
    
                macro_ptr = func_str.str;
                next();
                analyse_function();
#endif

                /* compute text section */
                cur_text_section = ad.section;
                if (!cur_text_section)
                    cur_text_section = text_section;
                ind = cur_text_section->data_offset;
                funcname = get_tok_str(v, NULL);
                sym = sym_find(v);
                if (sym) {
                    /* if symbol is already defined, then put complete type */
                    sym->t = t;
                } else {
                    /* put function symbol */
                    sym = sym_push1(&global_stack, v, t, 0);
                }
                /* NOTE: we patch the symbol size later */
                put_extern_sym(sym, cur_text_section, ind, 0);
                func_ind = ind;
                sym->r = VT_SYM | VT_CONST;
                /* put debug symbol */
                if (do_debug)
                    put_func_debug(sym);
                /* push a dummy symbol to enable local sym storage */
                sym_push1(&local_stack, 0, 0, 0);
                gfunc_prolog(t);
                loc = 0;
                rsym = 0;
#ifdef CONFIG_REG_VARS
                macro_ptr = func_str.str;
                next();
#endif
                block(NULL, NULL, NULL, NULL, 0);
                gsym(rsym);
                gfunc_epilog();
                cur_text_section->data_offset = ind;
                sym_pop(&label_stack, NULL); /* reset label stack */
                sym_pop(&local_stack, NULL); /* reset local stack */
                /* end of function */
                /* patch symbol size */
                ((Elf32_Sym *)symtab_section->data)[sym->c].st_size = 
                    ind - func_ind;
                if (do_debug) {
                    put_stabn(N_FUN, 0, 0, ind - func_ind);
                }
                funcname = ""; /* for safety */
                func_vt = VT_VOID; /* for safety */
                ind = 0; /* for safety */

#ifdef CONFIG_REG_VARS
                tok_str_free(func_str.str);
                restore_parse_state(&saved_parse_state);
#endif
                break;
            } else {
                if (b & VT_TYPEDEF) {
                    /* save typedefed type  */
                    /* XXX: test storage specifiers ? */
                    sym_push(v, t | VT_TYPEDEF, 0, 0);
                } else if ((t & VT_BTYPE) == VT_FUNC) {
                    /* external function definition */
                    external_sym(v, t, 0);
                } else {
                    /* not lvalue if array */
                    r = 0;
                    if (!(t & VT_ARRAY))
                        r |= lvalue_type(t);
                    if (b & VT_EXTERN) {
                        /* external variable */
                        external_sym(v, t, r);
                    } else {
                        if (t & VT_STATIC)
                            r |= VT_CONST;
                        else
                            r |= l;
                        has_init = (tok == '=');
                        if (has_init)
                            next();
                        decl_initializer_alloc(t, &ad, r, 
                                               has_init, v, l);
                    }
                }
                if (tok != ',') {
                    skip(';');
                    break;
                }
                next();
            }
        }
    }
}

/* compile the C file opened in 'file'. Return non zero if errors. */
static int tcc_compile(TCCState *s)
{
    Sym *define_start, *sym;
    char buf[512];
    int p, section_sym;

    funcname = "";
    include_stack_ptr = include_stack;
    ifdef_stack_ptr = ifdef_stack;

    /* XXX: not ANSI compliant: bound checking says error */
    vtop = vstack - 1;
    anon_sym = SYM_FIRST_ANOM; 

    /* file info: full path + filename */
    section_sym = 0; /* avoid warning */
    if (do_debug) {
        section_sym = put_elf_sym(symtab_section, 0, 0, 
                                  ELF32_ST_INFO(STB_LOCAL, STT_SECTION), 0, 
                                  text_section->sh_num, NULL);
        getcwd(buf, sizeof(buf));
        pstrcat(buf, sizeof(buf), "/");
        put_stabs_r(buf, N_SO, 0, 0, 
                    text_section->data_offset, text_section, section_sym);
        put_stabs_r(file->filename, N_SO, 0, 0, 
                    text_section->data_offset, text_section, section_sym);
    }
    /* an elf symbol of type STT_FILE must be put so that STB_LOCAL
       symbols can be safely used */
    put_elf_sym(symtab_section, 0, 0, 
                ELF32_ST_INFO(STB_LOCAL, STT_FILE), 0, 
                SHN_ABS, file->filename);

    /* define common 'char *' type because it is often used internally
       for arrays and struct dereference */
    char_pointer_type = mk_pointer(VT_BYTE);
    /* define an old type function 'int func()' */
    p = anon_sym++;
    sym = sym_push1(&global_stack, p, 0, FUNC_OLD);
    sym->r = FUNC_CDECL;
    func_old_type = VT_FUNC | (p << VT_STRUCT_SHIFT);

    define_start = define_stack.top;
    inp();
    ch = '\n'; /* needed to parse correctly first preprocessor command */
    next();
    decl(VT_CONST);
    if (tok != -1)
        expect("declaration");

    /* end of translation unit info */
    if (do_debug) {
        put_stabs_r(NULL, N_SO, 0, 0, 
                    text_section->data_offset, text_section, section_sym);
    }

    /* reset define stack, but leave -Dsymbols (may be incorrect if
       they are undefined) */
    sym_pop(&define_stack, define_start); 
    
    sym_pop(&global_stack, NULL);
    
    return 0;
}

int tcc_compile_string(TCCState *s, const char *str)
{
    BufferedFile bf1, *bf = &bf1;
    int ret;

    /* init file structure */
    bf->fd = -1;
    bf->buf_ptr = (char *)str;
    bf->buf_end = (char *)str + strlen(bf->buffer);
    pstrcpy(bf->filename, sizeof(bf->filename), "<string>");
    bf->line_num = 1;
    file = bf;
    
    ret = tcc_compile(s);
    
    /* currently, no need to close */
    return ret;
}

/* define a symbol. A value can also be provided with the '=' operator */
void tcc_define_symbol(TCCState *s, const char *sym, const char *value)
{
    BufferedFile bf1, *bf = &bf1;

    pstrcpy(bf->buffer, IO_BUF_SIZE, sym);
    pstrcat(bf->buffer, IO_BUF_SIZE, " ");
    /* default value */
    if (!value) 
        value = "1";
    pstrcat(bf->buffer, IO_BUF_SIZE, value);

    /* init file structure */
    bf->fd = -1;
    bf->buf_ptr = bf->buffer;
    bf->buf_end = bf->buffer + strlen(bf->buffer);
    bf->filename[0] = '\0';
    bf->line_num = 1;
    file = bf;
    
    include_stack_ptr = include_stack;

    /* parse with define parser */
    inp();
    ch = '\n'; /* needed to parse correctly first preprocessor command */
    next_nomacro();
    parse_define();
    file = NULL;
}

void tcc_undefine_symbol(TCCState *s1, const char *sym)
{
    TokenSym *ts;
    Sym *s;
    ts = tok_alloc(sym, 0);
    s = sym_find1(&define_stack, tok);
    /* undefine symbol by putting an invalid name */
    if (s)
        sym_undef(&define_stack, s);
}

#include "tccelf.c"

/* print the position in the source file of PC value 'pc' by reading
   the stabs debug information */
static void rt_printline(unsigned long wanted_pc)
{
    Stab_Sym *sym, *sym_end;
    char func_name[128], last_func_name[128];
    unsigned long func_addr, last_pc, pc;
    const char *incl_files[INCLUDE_STACK_SIZE];
    int incl_index, len, last_line_num, i;
    const char *str, *p;

    func_name[0] = '\0';
    func_addr = 0;
    incl_index = 0;
    last_func_name[0] = '\0';
    last_pc = 0xffffffff;
    last_line_num = 1;
    sym = (Stab_Sym *)stab_section->data + 1;
    sym_end = (Stab_Sym *)(stab_section->data + stab_section->data_offset);
    while (sym < sym_end) {
        switch(sym->n_type) {
            /* function start or end */
        case N_FUN:
            if (sym->n_strx == 0) {
                func_name[0] = '\0';
                func_addr = 0;
            } else {
                str = stabstr_section->data + sym->n_strx;
                p = strchr(str, ':');
                if (!p) {
                    pstrcpy(func_name, sizeof(func_name), str);
                } else {
                    len = p - str;
                    if (len > sizeof(func_name) - 1)
                        len = sizeof(func_name) - 1;
                    memcpy(func_name, str, len);
                    func_name[len] = '\0';
                }
                func_addr = sym->n_value;
            }
            break;
            /* line number info */
        case N_SLINE:
            pc = sym->n_value + func_addr;
            if (wanted_pc >= last_pc && wanted_pc < pc)
                goto found;
            last_pc = pc;
            last_line_num = sym->n_desc;
            /* XXX: slow! */
            strcpy(last_func_name, func_name);
            break;
            /* include files */
        case N_BINCL:
            str = stabstr_section->data + sym->n_strx;
        add_incl:
            if (incl_index < INCLUDE_STACK_SIZE) {
                incl_files[incl_index++] = str;
            }
            break;
        case N_EINCL:
            if (incl_index > 1)
                incl_index--;
            break;
        case N_SO:
            if (sym->n_strx == 0) {
                incl_index = 0; /* end of translation unit */
            } else {
                str = stabstr_section->data + sym->n_strx;
                /* do not add path */
                len = strlen(str);
                if (len > 0 && str[len - 1] != '/')
                    goto add_incl;
            }
            break;
        }
        sym++;
    }
    /* did not find line number info: */
    fprintf(stderr, "(no debug info, pc=0x%08lx): ", wanted_pc);
    return;
 found:
    for(i = 0; i < incl_index - 1; i++)
        fprintf(stderr, "In file included from %s\n", 
                incl_files[i]);
    if (incl_index > 0) {
        fprintf(stderr, "%s:%d: ", 
                incl_files[incl_index - 1], last_line_num);
    }
    if (last_func_name[0] != '\0') {
        fprintf(stderr, "in function '%s()': ", last_func_name);
    }
}

/* emit a run time error at position 'pc' */
void rt_error(unsigned long pc, const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);

    rt_printline(pc);
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
    exit(255);
    va_end(ap);
}

#ifndef WIN32
/* signal handler for fatal errors */
static void sig_error(int signum, siginfo_t *siginf, void *puc)
{
    struct ucontext *uc = puc;
    unsigned long pc;

#ifdef __i386__
    pc = uc->uc_mcontext.gregs[14];
#else
#error please put the right sigcontext field    
#endif

    switch(signum) {
    case SIGFPE:
        switch(siginf->si_code) {
        case FPE_INTDIV:
        case FPE_FLTDIV:
            rt_error(pc, "division by zero");
            break;
        default:
            rt_error(pc, "floating point exception");
            break;
        }
        break;
    case SIGBUS:
    case SIGSEGV:
        rt_error(pc, "dereferencing invalid pointer");
        break;
    case SIGILL:
        rt_error(pc, "illegal instruction");
        break;
    case SIGABRT:
        rt_error(pc, "abort() called");
        break;
    default:
        rt_error(pc, "caught signal %d", signum);
        break;
    }
    exit(255);
}
#endif

/* launch the compiled program with the given arguments */
int tcc_run(TCCState *s1, int argc, char **argv)
{
    Section *s;
    int (*prog_main)(int, char **);
    int i;

    tcc_add_runtime(s1);

    relocate_common_syms();

    /* compute relocation address : section are relocated in place. We
       also alloc the bss space */
    for(i = 1; i < nb_sections; i++) {
        s = sections[i];
        if (s->sh_flags & SHF_ALLOC) {
            void *data;
            if (s->sh_type == SHT_NOBITS) {
                data = tcc_mallocz(s->data_offset);
            } else {
                data = s->data;
            }
            s->sh_addr = (unsigned long)data;
        }
    }

    relocate_syms(1);

    /* relocate each section */
    for(i = 1; i < nb_sections; i++) {
        s = sections[i];
        if (s->reloc)
            relocate_section(s1, s);
    }

    prog_main = (void *)get_elf_sym_val("main");
    
    if (do_debug) {
#ifdef WIN32
        error("debug mode currently not available for Windows");
#else        
        struct sigaction sigact;
        /* install TCC signal handlers to print debug info on fatal
           runtime errors */
        sigact.sa_flags = SA_SIGINFO | SA_ONESHOT;
        sigact.sa_sigaction = sig_error;
        sigemptyset(&sigact.sa_mask);
        sigaction(SIGFPE, &sigact, NULL);
        sigaction(SIGILL, &sigact, NULL);
        sigaction(SIGSEGV, &sigact, NULL);
        sigaction(SIGBUS, &sigact, NULL);
        sigaction(SIGABRT, &sigact, NULL);
#endif
    }

#ifdef CONFIG_TCC_BCHECK
    if (do_bounds_check) {
        void (*bound_init)(void);
        void **bound_error_func;

        /* set error function */
        bound_error_func = (void **)get_elf_sym_val("__bound_error_func");
        *bound_error_func = rt_error;

        /* XXX: use .init section so that it also work in binary ? */
        bound_init = (void *)get_elf_sym_val("__bound_init");
        bound_init();
    }
#endif
    return (*prog_main)(argc, argv);
}

TCCState *tcc_new(void)
{
    char *p, *r;
    TCCState *s;

    s = tcc_malloc(sizeof(TCCState));
    if (!s)
        return NULL;
    s->output_type = TCC_OUTPUT_MEMORY;
    
    /* default include paths */
    tcc_add_sysinclude_path(s, "/usr/local/include");
    tcc_add_sysinclude_path(s, "/usr/include");
    tcc_add_sysinclude_path(s, CONFIG_TCC_PREFIX "/lib/tcc/include");

    /* add all tokens */
    tok_ident = TOK_IDENT;
    p = tcc_keywords;
    while (*p) {
        r = p;
        while (*r++);
        tok_alloc(p, r - p - 1);
        p = r;
    }

    /* we add dummy defines for some special macros to speed up tests
       and to have working defined() */
    sym_push1(&define_stack, TOK___LINE__, MACRO_OBJ, 0);
    sym_push1(&define_stack, TOK___FILE__, MACRO_OBJ, 0);
    sym_push1(&define_stack, TOK___DATE__, MACRO_OBJ, 0);
    sym_push1(&define_stack, TOK___TIME__, MACRO_OBJ, 0);
    sym_push1(&define_stack, TOK___FUNCTION__, MACRO_OBJ, 0);

    /* standard defines */
    tcc_define_symbol(s, "__STDC__", NULL);
#if defined(TCC_TARGET_I386)
    tcc_define_symbol(s, "__i386__", NULL);
#endif
#if defined(linux)
    tcc_define_symbol(s, "linux", NULL);
#endif
    /* tiny C specific defines */
    tcc_define_symbol(s, "__TINYC__", NULL);
    
    /* default library paths */
    tcc_add_library_path(s, "/usr/local/lib");
    tcc_add_library_path(s, "/usr/lib");
    tcc_add_library_path(s, "/lib");

    /* no section zero */
    dynarray_add((void ***)&sections, &nb_sections, NULL);

    /* create standard sections */
    text_section = new_section(".text", SHT_PROGBITS, SHF_ALLOC | SHF_EXECINSTR);
    data_section = new_section(".data", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
    bss_section = new_section(".bss", SHT_NOBITS, SHF_ALLOC | SHF_WRITE);

    /* symbols are always generated for linking stage */
    symtab_section = new_symtab(".symtab", SHT_SYMTAB, 0,
                                ".strtab",
                                ".hashtab", SHF_PRIVATE); 
    strtab_section = symtab_section->link;
    
    /* private symbol table for dynamic symbols */
    dynsymtab_section = new_symtab(".dynsymtab", SHT_SYMTAB, SHF_PRIVATE,
                                   ".dynstrtab", 
                                   ".dynhashtab", SHF_PRIVATE);
    return s;
}

void tcc_delete(TCCState *s)
{
    tcc_free(s);
}

int tcc_add_include_path(TCCState *s, const char *pathname)
{
    char *pathname1;
    
    pathname1 = tcc_strdup(pathname);
    dynarray_add((void ***)&include_paths, &nb_include_paths, pathname1);
    return 0;
}

int tcc_add_sysinclude_path(TCCState *s, const char *pathname)
{
    char *pathname1;
    
    pathname1 = tcc_strdup(pathname);
    dynarray_add((void ***)&sysinclude_paths, &nb_sysinclude_paths, pathname1);
    return 0;
}

static int tcc_add_file_internal(TCCState *s, const char *filename, int flags)
{
    const char *ext;
    Elf32_Ehdr ehdr;
    int fd;
    BufferedFile *saved_file;
    
    /* find source file type with extension */
    ext = strrchr(filename, '.');
    if (ext)
        ext++;

    /* open the file */
    saved_file = file;
    file = tcc_open(filename);
    if (!file) {
        if (flags & AFF_PRINT_ERROR) {
            error("file '%s' not found", filename);
        } else {
            file = saved_file;
            return -1;
        }
    }

    if (!ext || !strcmp(ext, "c")) {
        /* C file assumed */
        tcc_compile(s);
    } else {
        fd = file->fd;
        /* assume executable format: auto guess file type */
        if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
            error("could not read header");
        lseek(fd, 0, SEEK_SET);
        
        if (ehdr.e_ident[0] == ELFMAG0 &&
            ehdr.e_ident[1] == ELFMAG1 &&
            ehdr.e_ident[2] == ELFMAG2 &&
            ehdr.e_ident[3] == ELFMAG3) {
            file->line_num = 0; /* do not display line number if error */
            if (ehdr.e_type == ET_REL) {
                tcc_load_object_file(s, fd, 0);
            } else if (ehdr.e_type == ET_DYN) {
                tcc_load_dll(s, fd, filename, (flags & AFF_REFERENCED_DLL) != 0);
            } else {
                error("unrecognized ELF file");
            }
        } else if (memcmp((char *)&ehdr, ARMAG, 8) == 0) {
            file->line_num = 0; /* do not display line number if error */
            tcc_load_archive(s, fd);
        } else {
            /* as GNU ld, consider it is an ld script if not recognized */
            if (tcc_load_ldscript(s) < 0)
                error("unrecognized file type");
        }
    }
    tcc_close(file);
    file = saved_file;
    return 0;
}

void tcc_add_file(TCCState *s, const char *filename)
{
    tcc_add_file_internal(s, filename, AFF_PRINT_ERROR);
}

int tcc_add_library_path(TCCState *s, const char *pathname)
{
    char *pathname1;
    
    pathname1 = tcc_strdup(pathname);
    dynarray_add((void ***)&library_paths, &nb_library_paths, pathname1);
    return 0;
}

/* find and load a dll. Return non zero if not found */
/* XXX: add '-rpath' option support ? */
static int tcc_add_dll(TCCState *s, const char *filename, int flags)
{
    char buf[1024];
    int i;

    for(i = 0; i < nb_library_paths; i++) {
        snprintf(buf, sizeof(buf), "%s/%s", 
                 library_paths[i], filename);
        if (tcc_add_file_internal(s, buf, flags) == 0)
            return 0;
    }
    return -1;
}

/* the library name is the same as the argument of the '-l' option */
int tcc_add_library(TCCState *s, const char *libraryname)
{
    char buf[1024];
    int i;
    void *h;
    
    /* if we output to memory, then we simply we dlopen(). */
    if (s->output_type == TCC_OUTPUT_MEMORY) {
        /* Since the libc is already loaded, we don't need to load it again */
        if (!strcmp(libraryname, "c"))
            return 0;
        snprintf(buf, sizeof(buf), "lib%s.so", libraryname);
        h = dlopen(buf, RTLD_GLOBAL | RTLD_LAZY);
        if (!h)
            return -1;
        return 0;
    }
    
    /* first we look for the dynamic library if not static linking */
    if (!static_link) {
        snprintf(buf, sizeof(buf), "lib%s.so", libraryname);
        if (tcc_add_dll(s, buf, 0) == 0)
            return 0;
    }

    /* then we look for the static library */
    for(i = 0; i < nb_library_paths; i++) {
        snprintf(buf, sizeof(buf), "%s/lib%s.a", 
                 library_paths[i], libraryname);
        if (tcc_add_file_internal(s, buf, 0) == 0)
            return 0;
    }
    return -1;
}

int tcc_add_symbol(TCCState *s, const char *name, unsigned long val)
{
    add_elf_sym(symtab_section, val, 0, 
                ELF32_ST_INFO(STB_GLOBAL, STT_NOTYPE),
                SHN_ABS, name);
    return 0;
}

int tcc_set_output_type(TCCState *s, int output_type)
{
    s->output_type = output_type;

    /* if bound checking, then add corresponding sections */
#ifdef CONFIG_TCC_BCHECK
    if (do_bounds_check) {
        /* define symbol */
        tcc_define_symbol(s, "__BOUNDS_CHECKING_ON", NULL);
        /* create bounds sections */
        bounds_section = new_section(".bounds", 
                                     SHT_PROGBITS, SHF_ALLOC);
        lbounds_section = new_section(".lbounds", 
                                      SHT_PROGBITS, SHF_ALLOC);
    }
#endif

    /* add debug sections */
    if (do_debug) {
        /* stab symbols */
        stab_section = new_section(".stab", SHT_PROGBITS, 0);
        stab_section->sh_entsize = sizeof(Stab_Sym);
        stabstr_section = new_section(".stabstr", SHT_STRTAB, 0);
        put_elf_str(stabstr_section, "");
        stab_section->link = stabstr_section;
        /* put first entry */
        put_stabs("", 0, 0, 0, 0);
    }

    /* add libc crt1/crti objects */
    if (output_type == TCC_OUTPUT_EXE || 
        output_type == TCC_OUTPUT_DLL) {
        if (output_type != TCC_OUTPUT_DLL)
            tcc_add_file(s, CONFIG_TCC_CRT_PREFIX "/crt1.o");
        tcc_add_file(s, CONFIG_TCC_CRT_PREFIX "/crti.o");
    }
    return 0;
}

#if !defined(LIBTCC)

void help(void)
{
    printf("tcc version 0.9.10 - Tiny C Compiler - Copyright (C) 2001, 2002 Fabrice Bellard\n" 
           "usage: tcc [-c] [-o outfile] [-Bdir] [-bench] [-Idir] [-Dsym[=val]] [-Usym]\n"
           "           [-g] [-b] [-Ldir] [-llib] [-shared] [-static]\n"
           "           [--] infile1 [infile2... --] [infile_args...]\n"
           "\n"
           "General options:\n"
           "  -c          compile only - generate an object file\n"
           "  -o outfile  set output filename\n"
           "  --          allows multiples input files if no -o option given. Also\n" 
           "              separate input files from runtime arguments\n"
           "  -Bdir       set tcc internal library path\n"
           "  -bench      output compilation statistics\n"
           "Preprocessor options:\n"
           "  -Idir       add include path 'dir'\n"
           "  -Dsym[=val] define 'sym' with value 'val'\n"
           "  -Usym       undefine 'sym'\n"
           "C compiler options:\n"
           "  -g          generate runtime debug info\n"
#ifdef CONFIG_TCC_BCHECK
           "  -b          compile with built-in memory and bounds checker (implies -g)\n"
#endif
           "Linker options:\n"
           "  -Ldir       add library path 'dir'\n"
           "  -llib       link with dynamic or static library 'lib'\n"
           "  -shared     generate a shared library\n"
           "  -static     static linking\n"
           );
}

int main(int argc, char **argv)
{
    char *r, *outfile;
    int optind, output_type, multiple_files, i;
    TCCState *s;
    char **libraries;
    int nb_libraries;
    
    s = tcc_new();
    output_type = TCC_OUTPUT_MEMORY;

    optind = 1;
    outfile = NULL;
    multiple_files = 0;
    libraries = NULL;
    nb_libraries = 0;
    while (1) {
        if (optind >= argc) {
        show_help:
            help();
            return 1;
        }
        r = argv[optind];
        if (r[0] != '-')
            break;
        optind++;
        if (r[1] == '-') {
            /* '--' enables multiple files input */
            multiple_files = 1;
        } else if (r[1] == 'h' || r[1] == '?') {
            goto show_help;
        } else if (r[1] == 'I') {
            if (tcc_add_include_path(s, r + 2) < 0)
                error("too many include paths");
        } else if (r[1] == 'D') {
            char *sym, *value;
            sym = r + 2;
            value = strchr(sym, '=');
            if (value) {
                *value = '\0';
                value++;
            }
            tcc_define_symbol(s, sym, value);
        } else if (r[1] == 'U') {
            tcc_undefine_symbol(s, r + 2);
        } else if (r[1] == 'L') {
            tcc_add_library_path(s, r + 2);
        } else if (r[1] == 'B') {
            /* set tcc utilities path (mainly for tcc development) */
            tcc_lib_path = r + 2;
        } else if (r[1] == 'l') {
            dynarray_add((void ***)&libraries, &nb_libraries, r + 2);
        } else if (!strcmp(r + 1, "bench")) {
            do_bench = 1;
        } else 
#ifdef CONFIG_TCC_BCHECK
        if (r[1] == 'b') {
            do_bounds_check = 1;
            do_debug = 1;
        } else 
#endif
        if (r[1] == 'g') {
            do_debug = 1;
        } else if (r[1] == 'c') {
            multiple_files = 1;
            output_type = TCC_OUTPUT_OBJ;
        } else if (!strcmp(r + 1, "static")) {
            static_link = 1;
        } else if (!strcmp(r + 1, "shared")) {
            output_type = TCC_OUTPUT_DLL;
        } else if (r[1] == 'o') {
            if (optind >= argc)
                goto show_help;
            multiple_files = 1;
            outfile = argv[optind++];
        } else {
            error("invalid option -- '%s'", r);
        }
    }

    /* if outfile provided without other options, we output an
       executable */
    if (outfile && output_type == TCC_OUTPUT_MEMORY)
        output_type = TCC_OUTPUT_EXE;
    
    tcc_set_output_type(s, output_type);

    tcc_add_file(s, argv[optind]);
    if (multiple_files) {
        while ((optind + 1) < argc) {
            optind++;
            r = argv[optind];
            if (r[0] == '-') {
                if (r[1] != '-')
                    error("'--' expected");
                break;
            }
            tcc_add_file(s, r);
        }
    }

    /* add specified libraries */
    for(i = 0; i < nb_libraries;i++) {
        if (tcc_add_library(s, libraries[i]) < 0)
                error("cannot find -l%s", libraries[i]);
    }

    if (do_bench) {
        printf("total: %d idents, %d lines, %d bytes\n", 
               tok_ident - TOK_IDENT, total_lines, total_bytes);
#ifdef MEM_DEBUG
        printf("memory: %d bytes, max = %d bytes\n", mem_cur_size, mem_max_size);
#endif
    }

    if (s->output_type != TCC_OUTPUT_MEMORY) {
        tcc_output_file(s, outfile);
        return 0;
    } else {
        return tcc_run(s, argc - optind, argv + optind);
    }
}

#endif