From c025478d7c03eb8d32022f1aec4537bd0a75a743 Mon Sep 17 00:00:00 2001
From: mingodad <mingodad@gmail.com>
Date: Fri, 28 Mar 2014 20:28:19 +0000
Subject: [PATCH] New implementation of va_list/va_start/var_copy that do not
 use dynamic memory, with this when compiling fossil-scm with tcc on linux
 X86_64 it works fine.

---
 include/stdarg.h | 28 +++++++++++++++++++---------
 lib/libtcc1.c    | 30 +++++++++---------------------
 2 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/include/stdarg.h b/include/stdarg.h
index 3c1318e..b6a30f7 100644
--- a/include/stdarg.h
+++ b/include/stdarg.h
@@ -4,18 +4,28 @@
 #ifdef __x86_64__
 #ifndef _WIN64
 
-typedef void *va_list;
+//This should be in sync with the declaration on our lib/libtcc1.c
+/* GCC compatible definition of va_list. */
+typedef struct {
+    unsigned int gp_offset;
+    unsigned int fp_offset;
+    union {
+        unsigned int overflow_offset;
+        char *overflow_arg_area;
+    };
+    char *reg_save_area;
+} __va_list_struct;
 
-va_list __va_start(void *fp);
-void *__va_arg(va_list ap, int arg_type, int size, int align);
-va_list __va_copy(va_list src);
-void __va_end(va_list ap);
+typedef __va_list_struct va_list;
 
-#define va_start(ap, last) ((ap) = __va_start(__builtin_frame_address(0)))
+void __va_start(__va_list_struct *ap, void *fp);
+void *__va_arg(__va_list_struct *ap, int arg_type, int size, int align);
+
+#define va_start(ap, last) __va_start(&ap, __builtin_frame_address(0))
 #define va_arg(ap, type)                                                \
-    (*(type *)(__va_arg(ap, __builtin_va_arg_types(type), sizeof(type), __alignof__(type))))
-#define va_copy(dest, src) ((dest) = __va_copy(src))
-#define va_end(ap) __va_end(ap)
+    (*(type *)(__va_arg(&ap, __builtin_va_arg_types(type), sizeof(type), __alignof__(type))))
+#define va_copy(dest, src) ((dest) = (src))
+#define va_end(ap)
 
 #else /* _WIN64 */
 typedef char *va_list;
diff --git a/lib/libtcc1.c b/lib/libtcc1.c
index a5896a4..284965e 100644
--- a/lib/libtcc1.c
+++ b/lib/libtcc1.c
@@ -626,10 +626,12 @@ long long __fixxfdi (long double a1)
 #ifndef __TINYC__
 #include <stdlib.h>
 #include <stdio.h>
+#include <string.h>
 #else
 /* Avoid including stdlib.h because it is not easily available when
    cross compiling */
 extern void *malloc(unsigned long long);
+void *memset(void *s, int c, size_t n);
 extern void free(void*);
 extern void abort(void);
 #endif
@@ -638,8 +640,9 @@ enum __va_arg_type {
     __va_gen_reg, __va_float_reg, __va_stack
 };
 
+//This should be in sync with the declaration on our include/stdarg.h
 /* GCC compatible definition of va_list. */
-struct __va_list_struct {
+typedef struct {
     unsigned int gp_offset;
     unsigned int fp_offset;
     union {
@@ -647,24 +650,22 @@ struct __va_list_struct {
         char *overflow_arg_area;
     };
     char *reg_save_area;
-};
+} __va_list_struct;
 
 #undef __va_start
 #undef __va_arg
 #undef __va_copy
 #undef __va_end
 
-void *__va_start(void *fp)
+void __va_start(__va_list_struct *ap, void *fp)
 {
-    struct __va_list_struct *ap =
-        (struct __va_list_struct *)malloc(sizeof(struct __va_list_struct));
-    *ap = *(struct __va_list_struct *)((char *)fp - 16);
+    memset(ap, 0, sizeof(__va_list_struct));
+    *ap = *(__va_list_struct *)((char *)fp - 16);
     ap->overflow_arg_area = (char *)fp + ap->overflow_offset;
     ap->reg_save_area = (char *)fp - 176 - 16;
-    return ap;
 }
 
-void *__va_arg(struct __va_list_struct *ap,
+void *__va_arg(__va_list_struct *ap,
                enum __va_arg_type arg_type,
                int size, int align)
 {
@@ -701,19 +702,6 @@ void *__va_arg(struct __va_list_struct *ap,
     }
 }
 
-void *__va_copy(struct __va_list_struct *src)
-{
-    struct __va_list_struct *dest =
-        (struct __va_list_struct *)malloc(sizeof(struct __va_list_struct));
-    *dest = *src;
-    return dest;
-}
-
-void __va_end(struct __va_list_struct *ap)
-{
-    free(ap);
-}
-
 #endif /* __x86_64__ */
 
 /* Flushing for tccrun */