Like returned local variables also labels local to a statement expression
can be returned, and so their symbols must not be immediately freed
(though they need to be removed from the symbol table).
Use 2 level strategy to access packed bitfields cleanly:
1) Allow to override the original declaration type with
an auxilary "access type". This solves cases such as
struct {
...
unsigned f1:1;
};
by using VT_BYTE to access f1.
2) Allow byte-wise split accesses using two new functions
load/store_packed_bf. This solves any cases, also ones
such as
struct __attribute((packed)) _s {
unsigned x : 12;
unsigned char y : 7;
unsigned z : 28;
unsigned a: 3;
unsigned b: 3;
unsigned c: 3;
};
where for field 'z':
- VT_INT access from offset 2 would be unaligned
- VT_LLONG from offset 0 would go past the total
struct size (7)
and for field 'a' because it is in two bytes and
aligned access with VT_SHORT/INT is not possible.
Also, static bitfield initializers are stored byte-wise always.
Also, cleanup the struct_layout function a bit.
That means: we do not macro-expand the argument of 'defined'
Also: store the last token position into the TokenString
structure in order to get rid of the tok_last function.
This requires one more change in how macro arguments are expanded:
the standard requires that macro args are expanded before substituting
into the replacement list. This implies expanding them only once
even when they occur multiple times in the list. TCC expanded
them repeatedly in that case. Without __COUNTER__ that's harmless.
So, simply always expand arguments (when used without # and ##) once
and store the resulting tokens.
See added testcase 19.c from a bug report. The problem is reading outside
the arguments buffers, even though we aren't allowed to. The single
can_read_stream variable is not enough, sometimes we need to be able
to pop into outer contexts but not into arbitrarily outside contexts.
The trick is to terminate argument tokens with a EOF (and not just with
0 that makes us pop contexts), and deal with that in the few places
we have to,
This enables some cleanups of the can_read_stream variable use.
If there were more than 6 integer arguments before the ellipsis, or
there were used more than 8 slots used until the ellipsis (e.g. by
a large intermediate struct) we generated wrong code. See testcase.
- configure:
- add --config-uClibc,-musl switch and suggest to use
it if uClibc/musl is detected
- make warning options magic clang compatible
- simplify (use $confvars instead of individual options)
- Revert "Remove some unused-parameter lint"
7443db0d5f
rather use -Wno-unused-parameter (or just not -Wextra)
- #ifdef functions that are unused on some targets
- tccgen.c: use PTR_SIZE==8 instead of (X86_64 || ARM64)
- tccpe.c: fix some warnings
- integrate dummy arm-asm better
For integer promotion with for example arithmetics or
expr_cond (x ? y : z), integral types need to be promoted
to signed if they fit.
According to latest standards, this also applies to bit-field
types taking into account their specific width.
In tcc, VT_BITFIELD set means width < original type width
Field-widths between 33 and 63 are promoted to signed long long
accordingly.
struct { unsigned long long ullb:35; } s = { 1 };
#define X (s.ullb - 2)
int main (void)
{
long long Y = X;
printf("%d %016llx %016llx\n", X < 0, -X, -Y);
return 0;
}
Results:
GCC 4.7 : 0 0000000000000001 FFFFFFF800000001
MSVC : 1 0000000000000001 0000000000000001
TCC : 1 0000000000000001 0000000000000001
Also, gcc would promote long long bitfields of size < 32
to int as well. Example:
struct { unsigned long long x:20; } t = { 123 };
/* with gcc: */ printf("%d %d\n", t.x, 456);
/* with tcc: */ printf("%lld %d\n", t.x, 456);
* tccgen: re-allow long double constants for x87 cross
sizeof (long double) may be 12 or 16 depending on host platform
(i386/x86_64 on unix/windows).
Except that it's 8 if the host is on windows and not gcc
was used to compile tcc.
* win64: fix builtin_va_start after VT_REF removal
See also a8b83ce43a
* tcctest.c: remove outdated limitation for ll-bitfield test
It always worked, there is no reason why it should not work
in future.
* libtcc1.c: exclude long double conversion on ARM
* Makefile: remove CFLAGS from link recipes
* lib/Makefile: use target DEFINES as passed from main Makefile
* lib/armflush.c lib/va_list.c: factor out from libtcc1.c
* arm-gen.c: disable "depreciated" warnings for now
'extern int i = 42;' at file scope (but not in function scope!) is
allowed and is a proper definition, even though questionable style;
some compilers warn about this.
See the added testcase. When one used designators like .a.x to initialize
sub-members of members, and didn't then initialize all of them the
required zero-initialization of the other sub-members wasn't done.
The fix also enables tiny code cleanups.
See testcase. If an enum has only positive values, fits N bits,
and is placed in a N-bit bit-field that bit-fields must be treated
as unsigned, not signed.
This invalid function definition:
int f()[] {}
was tried to be handled but there was no testcase if it actually worked.
This fixes it and adds a TCC only testcase.
factor code a bit for transforming tokens into SValues. This revealed
a bug in TOK_GET (see testcase), which happened to be harmless before.
So fix that as well.
Our code generation assumes that it can load/store with the
bit-fields base type, so bit_pos/bit_size must be in range for this.
We could change the fields type or adjust offset/bit_pos; we do the
latter.
Checked the lcc testsuite for bitfield stuff (in cq.c and fields.c),
fixed one more error in initializing unnamed members (which have
to be skipped), removed the TODO.
- configure/Makefiles: minor adjustments
- build-tcc.bat: add -static to gcc options
(avoids libgcc_s*.dll dependency with some mingw versions)
- tccpe.c/tcctools.c: eliminate MAX_PATH
(not available for cross compilers)
- tccasm.c: use uint64_t/strtoull in unary()
(unsigned long sometimes is only uint32_t, as always on windows)
- tccgen.c: Revert (f077d16c) "tccgen: gen_cast: cast FLOAT to DOUBLE"
Was a rather experimental, tentative commit, not really necessary
and somewhat ugly too.
- cleanup recent osx support:
- Makefile/libtcc.c: cleanup copy&paste code
- tccpp.c: restore deleted function
Arg substitution leaves placeholder marker in the stream for
empty arguments. Those need to be skipped when searching for
a fnlike macro invocation in the replacement list itself. See
testcase.
Commit bb93064 changed the path seperator from ':' to ';', which was
likely accidental. While path seperator on Windows is generally ';', the
Makefile clearly expects a posix-y shell, and in such environments the
separator is ':'.
This fixes the test run in MSYS2 and MSYS(1) environments, which got
broken on bb93064 .
supports building cross compilers on the fly without need
for configure --enable-cross
$ make cross # all compilers
$ make cross-TARGET # only TARGET-compiler & its libtcc1.a
with TARGET one from
i386 x86_64 i386-win32 x86_64-win32 arm arm64 arm-wince c67
Type 'make help' for more information
the avoidance of mov im32->reg64 wasn't working when reg64 was rax.
While fixing this also fix instructions which had the REX prefix
hardcoded in opcode and so didn't support extended registers which
would have added another REX prefix.
Forgot about it. It allows to compile several
sources (and other .o's) to one single .o file;
tcc -r -o all.o f1.c f2.c f3.S o4.o ...
Also:
- option -fold-struct-init-code removed, no effect anymore
- (tcc_)set_environment() moved to tcc.c
- win32/lib/(win)crt1 minor fix & add dependency
- debug line output for asm (tcc -c -g xxx.S) enabled
- configure/Makefiles: x86-64 -> x86_64 changes
- README: cleanup
usage:
tcc -ar [rcsv] lib files...
tcc -impdef lib.dll [-v] [-o lib.def]
also:
- support more files with -c: tcc -c f1.c f2.c ...
- fix a bug which caused tcc f1.c f2.S to produce no asm
- allow tcc -ar @listfile too
- change prototype: _void_ tcc_set_options(...)
- apply -Wl,-whole-archive when a librariy is given
as libxxx.a also (not just for -lxxx)
- lib/Makefile: add (win)crt1_w.o
- crt1.c/_runtmain: return to tcc & only use for UNICODE
(because it might be not 100% reliable with for example
wildcards (tcc *.c -run ...)
- tccrun.c/tccpe.c: load -run startup_code only if called
from tcc_run(). Otherwise main may not be defined. See
libtcc_test.c
- tests2/Makefile: pass extra options in FLAGS to allow
overriding TCC
Also:
- tccpe.c: support weak attribute. (I first tried to solve
the problem above by using it but then didn't)
Also:
- in tests: generate .expect files only if not yet present,
because
1) some files were adjusted manually
2) switching git branche might change timestamps and
cause unwanted update
tests/Makefile: fix out-of-tree build issues
Also:
- win64: align(16) MEM_DEBUG user memory
on win64 the struct jmp_buf in the TCCState structure which we
allocate by tcc_malloc needs alignment 16 because the msvcrt
setjmp uses MMX instructions.
- libtcc_test.c: win32/64 need __attribute__((dllimport)) for
extern data objects
- tcctest.c: exclude stuff that gcc does not compile
except for relocation_test() the other issues are mostly ASM
related. We should probably check GCC versions but I have
no idea which mingw/gcc versions support what and which don't.
- lib/Makefile: use tcc to compile libtcc1.a (except on arm
which needs arm-asm
Some more subtle issues with code suppression:
- outputting asms but not their operand setup is broken
- but global asms must always be output
- statement expressions are transparent to code suppression
- vtop can't be transformed from VT_CMP/VT_JMP when nocode_wanted
Also remove .exe files from tests2 if they don't fail.
Also ...
tcctest.c:
- exclude stuff that gcc doesn't compile on windows.
libtcc.c/tccpp.c:
- use unsigned for memory sizes to avoid printf format warnings
- use "file:line: message" to make IDE error parsers happy.
tccgen.c: fix typo
on 32bit long long support was sometimes broken. This fixes
code-gen for long long values in switches, disables a x86-64 specific
testcase and avoid an undefined shift amount. It comments out
a bitfield test involving long long bitfields > 32 bit; with GCC layout
they can straddle multiple words and code generation isn't prepared
for this.
when an alignment is explicitely given on the member itself,
or on its types attributes then respect it always. Was only
allowed to increase before, but GCC is allowing it.
The linux kernel has some structures that are page aligned,
i.e. 4096. Instead of enlarging the bit fields to specify this,
use the fact that alignment is always power of two, and store only
the log2 minus 1 of it. The 5 bits are enough to specify an alignment
of 1 << 30.
Such struct decl:
struct S { char a; int i;} __attribute__((packed));
should be accepted and cause S to be five bytes long (i.e.
the packed attribute should matter). So we can't layout
the members during parsing already. Split off the offset
and alignment calculation for this.
See testcases. We now support 64bit case constants. At the same time
also 64bit enum constants on L64 platforms (otherwise the Sym struct
isn't large enough for now). The testcase also checks for various
cases where sign/zero extension was confused.
See testcase. We must always paste tokens (at least if not
currently substing a normal argument, which is a speed optimization
only now) but at the same time must not regard a ## token
coming from argument expansion as the token-paste operator, nor
if we constructed a ## token due to pasting itself (that was already
checked by pp/01.c).
In certain very specific situations (involving switches
with asms inside dead statement expressions) we could generate
invalid code (clobbering the buffer so much that we generated
invalid instructions). Don't emit the decision table if the
switch itself is dead.
The callee saved registers (among them r12-r15) really need
saving/restoring if mentioned in asm clobbers, even if TCC
itself doesn't use them. E.g. the linux kernel relies on that
in its switch_to() implementation.
When intializing members where the initializer needs relocations
and the member is initialized multiple times we can't allow
that to lead to multiple relocations to the same place. The last
one must win.
