Make code more compatible with gcc. Change
__atomic_store
__atomic_load
__atomic_exchange
__atomic_compare_exchange
Also add (include/stdatomic.h, lib/stdatomic.c):
atomic_thread_fence
atomic_signal_fence
atomic_is_lock_free
And gcc extensions (tcctok.h, tccgen.c, lib/stdatomic.c):
__atomic_fetch_nand
__atomic_and_fetch
__atomic_sub_fetch
__atomic_or_fetch
__atomic_xor_fetch
__atomic_and_fetch
__atomic_nand_fetch
Add new file lib/atomic.S with assembly code for __atomic_compare_exchange_n
for arm/arm64/riscv. Also update lib/Makefile.
Update testcode in 124_atomic_counter and 125_atomic_misc to test new functions.
Also update tests/tests2/Makefile to run tests on arm/arm64/riscv.
Bad assumption make bad things happen:
long d3;
asm(..."1:\tdec %3\n\t" : ... "=&c" (d3)
Which wants 'dec RDI' but did 'dec EDI' on _WIN64.
Also:
- tcctest.c: enable more asm tests for win64
- configure: show errors if any with 'gcc conftest.c'
- tccgen.c: remove decl0(x, y, z)
(As long as it is in the default install location and was not
moved elsewhere into the library search path manually)
Also:
- libtcc.c:
- error1(): show correct line with "In file included from ..."
- support "tcc -Bxxx -vv"
- tcc_new()/tcc_compile(): Don't create elf sections for tcc -E
- tccdbg.c:
- tcc -E -g : revert 1de025c13a
Let's keep things simple, everybody understands 'do_debug'
and dState is set by tcov too (but no debug sections).
- tccgen.c:
- avoid the extra parameter for gind()
(from c3e3a07ed4)
- vla func params: use skip_or_save_block() and enable
VT_LVAL (see 313855c232)
- cleanup nocode_wanted a bit
- tccelf.c:
- tccelf_end_file(): don't try to translate zero-sym relocs
(seems to happen with asm "jmp 0x1000")
- version_add(): do not make "ld-linux.so" DT_NEEDED
1) recursive types have no storage anymore, so a
static int (*p)[x];
declaration is just fine
2) since somewhen VT_VLA doesn't imply VT_ARRAY anymore, so we
now need to check VLA in at least one place before checking
test_lvalue.
((2) should probably be cleaned up again so that VLA does again imply
ARRAY)
- also simplify parse(_line)_comment() and parse_pp_string()
- fixes a continuation problem in strings (see tcctest.c)
- no differences in performance could be observed
161 insertions(+), 246 deletions(-), less 85 lines
an expression like 'i*0', even though it's value is constant and
can be evaluated at compile time is not an integer constant expression,
and hence no null pointer constant, and therefore the conditional
operator doesn't select the other type.
if a switch is unreachable then so are the case labels.
Unlike normal labels they can't possibly be reached from not-yet
parsed code, so there's no reason to enable codegen again for those.
they look similar to labels 'foobar : 32' (when foobar is a typedef),
but cannot be handled as such in parse_btype, the context is important
(labels can only happen when called from within 'block', aka decl0 in
VT_LOCAL context). This got broken back in 2019 (1b57560).
On an armeabi-v7a device (phone) in the termux app with
clang & make installed this passes all the tests.
Can be used as a cross compiler to create "native apps" as well.
Example 'config-extra.mak' for the cross arm-eabi-tcc:
SYSROOT = <path_to_android_ndk...>/sysroot/usr
TRIPLET = arm-linux-androideabi
ANDRVER = 32
ROOT-arm-eabi = $(SYSROOT)
CRT-arm-eabi = {R}/lib/$(TRIPLET)/$(ANDRVER)
LIB-arm-eabi = {B};{R}/lib/$(TRIPLET)/$(ANDRVER);{R}/lib/$(TRIPLET)
INC-arm-eabi = {B}/lib/include;{R}/include/$(TRIPLET);{R}/include
DEF-arm-eabi = -DTCC_TARGET_ARM -DTCC_ARM_VFP -DTCC_ARM_EABI
DEF-arm-eabi += -DTARGETOS_ANDROID -DCONFIG_TCC_PIE -DCONFIG_NEW_DTAGS
DEF-arm-eabi += -DCONFIG_TCC_ELFINTERP=\"/system/bin/linker\"
# on unix replace ';' by ':'.
$ ./configure && make cross-arm-eabi && make install
seems that symbols under nocode/NODATA should not produce
elf symbols at all, not just elf symbols with no size.
See commit 4c82b00342
5 insertions(+), 5 deletions(-)
See commit e588b65390.
Was not "wrong" really, just different. But appears to be outdated.
Now disabled by default (top of tccpp.c: ACCEPT_LF_IN_STRINGS)
Also, in skipped code, just warn.
Also: cleanup "Optimize small structure copying on x86_64"
(commit 3715f1d7ee)
- remove some copy&paste coding (tccgen.c)
- RSI/RDI need to be preserved on windows
- simply don't use under bcheck (this is tinycc)
commit ec5d94291 made is to that the nocode_wanted state from
inside a statement expression is retained after it. That is wrong
if the statement expression can't be entered to start with. In the
latter case the state from before the stmt-expr is the one we need.
tccgen.c:
- When __FUNCTION__ is used and no code is generated use symbol len = 0.
tccelf.c:
- If library is present in verneed it should be in DT_NEEDED.
- @plt symbols should have size 0
- set _GLOBAL_OFFSET_TABLE_ st_size correct
- Remove version symbol if new value present
reported by elflint:
__FUNCTION__ problem:
section [19] '.symtab': symbol 2134 (L.195) does not fit completely in referenced section [14] '.data.ro'
DT_NEEDED problem:
section [26] '.gnu.version_r': entry 2 references unknown dependency
@plt symbols should have size 0:
section [22] '.symtab': symbol 36557 (r_core_config_init@plt) does not fit completely in referenced section [14] '.plt'
_GLOBAL_OFFSET_TABLE_ size:
section [44] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol size 4 does not match .got section size 736
Remove version symbol:
section [25] '.gnu.version': symbol 86: version index 3 is for requested version
This happened for example with bounds checking symbol malloc
Better avoid global variables, at least in new code.
tccdbg.c hopefully should be logically identical to the
former parts in tccgen/elf.c (s1 tccstate added in some
places)
tccelf.c: dwarf linkage seems special per dwarf rather
than special per target.
/* Use "-g" as alias for "-g1". Use "-g0" to disable debug */
So not using -g is now the alias for -g0 ?!?
This reverts commit 8759b2581d.
This reverts commit 3ce7bc6efc.
This reverts commit 5fb582ab7f.
This reverts commit aea68dbb40.
This reverts commit fa9c31c3db.
This reverts commit b3bebdb20a.
This reverts commit ecf8e5a00e.
This reverts commit fe6b5c08dc.
This reverts commit e2e5377e7b.
This reverts commit 1cd7998905.
readelf complained about DW_AT_stmt_list and DW_AT_location.
For dwarf >= 4 we should use DW_FORM_sec_offset instead of DW_FORM_data4
and DW_FORM_exprloc instead of DW_FORM_block1.
This is fixed in tccgen.c
I also updated tccrun.c to use dwarf_read_1 instead of DW_GETC.
tccgen.c:
- add anon support. So tcc_state in tcc works now.
- add function pointer support
- remove DW_FORM_implicit_const from DW_TAG_pointer_type
tccrun.c:
- set initial file name
- correctly use pc in DW_LNE_set_address (see lib/bt-exe.c)
- add DW_LNE_define_file support (even if it is deprecated)
tccelf.c
- do not include debug/test_coverage information for stub functions
lib/bt-exe.c
- use num_callers=-1 to mark dll
The new gcc12 release does not support stabs any more.
This was a good reason to add support for dwarf.
The stabs code still works and is used if configure option --dwarf
is not used.
Tested on x86_64, i386, arm, arm64, riscv64 with dwarf-5.
Some debuggers may not support dwarf-5. Try using older dwarf versions
i that case.
The tccmacho.c code probably need some support for dwarf.
arm-gen.c, arm64-gen.c, i386-gen.c, riscv64-gen.c, x86_64-gen.
- fix get_sym_ref symbol size
arm-link.c, arm64-link.c, i386-link.c, riscv64-link.c, x86_64-link.c
- add R_DATA_32U
libtcc.c:
- parse -gdwarf option
tcc.c:
- add dwarf option
tcc.h:
- add dwarf option and sections
tccelf.c:
- init dwarf sections
- avoid adding sh_addr for dwarf sections
- remove dwarf relocs for output dll
- add dwarf sections for tccrun
tccgen.c:
- add dwarf defines + global data
- add dwarf_* functions
- mix dwarf code with stabs code
- a trick is used to emit function name in .debug_line section so
only this section has to be parsed instead of .debug_info and
.debug_abbrev.
- fix init debug_modes
tccrun.c:
- add dwarf sections in rt_context
- init them in tcc_run
- add new dwarf code rt_printline_dwarf to find file/function
dwarf.h:
- New file
tcc-doc.texi:
- document dwarf
configure:
- add dwarf option
lib/Makefile
- change -gstabs into -gdwarf
lib/bt-exe.c, tests/tests2/Makefile, tests/tests2/126_bound_global:
- Add __bound_init call
- Add new testcase to test it
Warnings reported in in x86_64-gen.c and arm-gen.c:
warning: ‘align’ may be used uninitialized in this function [-Wmaybe-uninitialized]
Signed-off-by: Detlef Riekenberg <wine.dev@web.de>
There is no code generation in post_type for vla arrays. This code
generation has to be delayed until gen_function.
- post_type save code in type info.
- gen_function use this code to generate vla code.
- enable testcode for vla arrays.
Modify function parameter parser such that symbols are
put into token-table temporarily. Benefits are:
- detects redefinitions, as with
int foo(int a, int a);
- detects reserved symbols, as with
int foo(int if);
- can parse expressions like
int main(int argc, char *argv[argc + 1]);
- doesn't fix this one
int main(int argc, char *argv[++argc]);
Also: fix unexpected "function might return no value"
with statement expression
int f() { ({ return 0; }); }
Currently used only with 'tcc_compile_sem' to protect
tcc_compile(), but can be used with other semaphores
Also fix deadlock when tcc_enter_state() is called
recursively for the same state, for example with
tcc_warning() from #pragma comment(option,"...")
Also:
- libtcc.c: error1(): use cstr_[v]printf()
- tcc.h: set TCC_USING_DOUBLE_FOR_LDOUBLE for macho-arm64
(rather than for macho-X86_64)
- tcc.h: define TCC_TARGET_MACHO on __APPLE__ by default
- tcc.h: cleanup TCCState, move DEFASM token stuff to tcctok.h
- tccgen.c: more static
- Makefile/tcc.c: review githash
- tccpe/tcctools: use read() instead of fgets() in pe_load_def()
(all files opened by tcc for reading are now read via 'int fd')
- configure/win32: don't preset CONFIG_TCCDIR (to allow to override it)
- tcc.c -bench: do not include output/run-time
136 insertions(+), 226 deletions(-), less 90 lines (except tests)
only one set_flag() function required
* can now turn off specific errors: -Werror -Wno-error=option
* new interface: tcc_warning_c(warn_option)("format", args...);
* new warning: -Wdiscarded-qualifiers (on by default)
* new variable 'warn_all' for conditional warnings with -Wall
see also the tests
configure:
- re-enable apple M1-arm64
- however, with --cpu=x86_64, set -arch in CFLAGS/LDFLAGS too
(assume rosetta)
Makefile:
- re-enable osx cross-test (Please do not disable tests)
tcc.h
- set TCC_IS_NATIVE for TCC_TARGET_MACHO on __APPLE__
- apply TCC_USING_DOUBLE_FOR_LDOUBLE for x86_64-osx
libtcc.c:
- cleanup tcc_add_file_internal()
- new function char *tcc_load_text(int fd); and use it for tbd files
- remove any error messages that were just for debugging the
templates really
- don't use c99 in tcc (array designators etc.)
- remove memory model type (cannot be an own type really)
and move memory model defines from built-in to stdatomics.h
- apply normal casts to non-pointer atomic_function arguments
- tidy the library support
- add some tests for errors/warnings
Also:
- Makefile: move GIT_HASH stuff from CFLAGS to DEFINES and into
main section (away from what is included by tests for example)
- tccelf.c/tccgen.c: avoid some warnings with newer GCC
Some complex types can still be small and simple enough to fit into
register. Other compilers allow some operations on these types, and it
seems to be quite a reasonable choice. From now on, we should be able
to compile the following artificial example:
struct combo {
uint16_t lo;
uint16_t hi;
};
struct combo load(const _Atomic(struct combo) *atom)
{
return atomic_load(atom);
}
void store(_Atomic(struct combo) *atom, struct combo value)
{
atomic_store(atom, value);
}
struct combo xchg(_Atomic(struct combo) *atom, struct combo value)
{
return atomic_exchange(atom, value);
}
bool cmpxchg(_Atomic(struct combo) *atom,
struct combo *cmp, struct combo xchg)
{
return atomic_compare_exchange_strong(atom, cmp, xchg);
}
This might be useful for some corner cases, though it is quite likely
that many programmers will prefer operating on a single 32-bit value
instead of using the structure consisting of 16-bit pair.
Things will work as long as the overall structure size happens to be
the same as for any integer type we support in atomics.
libtcc.c: add -Wwrite-strings to -Wall
tccgen.c: ro float-consts, string-consts, ro arrays if base type is
tccpe.c: merge IAT with rodata
tccrun.c: mprotect rodata accordingly. free section data after copy
x86_64.c: do not use got for static data.
tcc -bench: show data.rw/ro
Probably STB_LOCAL should never get to put_got_entry(), and currently
it doesn't seem to happen (See "Hack Alarm" there)
Other files: use more ro-data in tinycc
when used with string initialization the size of nested struct flex
array member was tested too late for < 0.
GCC accepts but discards such initializers (the flex array member will
become zero sized). TCC supports flex arrays members only in
top-level structs and gives an error in this case.
When defining an array with non-explicit size, one would get
"incompatible types for redefinition of 'array' if the array was already
declared with a different size.
For example:
extern int array[2];
int array[] = {1};
would fail to compile with tcc. Instead the above is now equivalent to:
int array[] = {1, 0};
this change fixes building of invalid types. The inner scope
struct P is return type of the forward decl foobar. The outer scope
foobar() call implicitely declares that function again, with int
return type; overall this leads to access within the sym free list,
effectively building up a type directly referring to itself, leading
to endless recursion later. The testcase is:
void n(void)
{
{
struct P {
int __val;
};
struct P foobar(); // 1
}
foobar(); // 2
}
I've not included it in tests2 for now, because tcc accepts this.
Ideally we would like to reject it (as 'int foobar();' is incompatible
with the earlier decl). clang also accepts it, but only because it's
not handling (1) above as an implicit decl of foobar (it warns, and
with -pedantic also warns about the type incompatiblity). GCC rejects
this.
Implementing that in tcc requires some surgery, as we need to differ
between these cases:
{ struct P foo(int); // 1
foo(); // no implicit decl, call to foo from 1
}
and
{ { struct P foo(int); // 2 }
foo(); // implicit decl, _incompatible_ with 2
}
normally the sym slot is meaningful only with VT_SYM. But we also
use it when mentioning a decl for inline asms with register vars,
conditional on being a VT_LOCAL entry. So when generating VT_LOCAL we
need to reset .sym as it might contain stale entries from the cmp_op
fields.
see testcase, reduced example of a situation reported by
Kyryl Melekhin in https://github.com/kyx0r/neatvi/ .
Problem is that setting up the VLA sp-save in a scope that isn't
entered at runtime leaves traces of it in outer scopes that then
try to restore the stack pointer from uninitialized slots.
Add myself to RELICENSING file
Use locking when writing tcov file
Fixed sometimes last line of function not shown
Merge tcc_tcov_add_file and tcc_add_tcov
Allow absolute file names
Count case labels with no code better
lib/tcov.c:
- can't be cross-compiled (needs stdio.h)
- can be included in libtcc1.a
Reason why bt-xxx.o/bcheck.o are linked separatly is because we
don't want then to linked into exe's and dlls at the same time.
tccgen.c: debug_modes
- don't waste debug function calls during normal execution.
libtcc.c:
- mem_debug: no C99 features in tcc please, for example
({compound expressions}): do not use.
tccgen.c: struct_layout:
- unaligned access is completely ok for most targets.
- Moreover the patch was triggering single byte mode even
for normal aligned access (as with tcc's SymAttr)
static Sym label: don't do this
arm-gen.c:
- use some #ifdefs to explain some code
tccpp.c:
- cleanup UCN chars
libtcc.c:
- replace openbsd library search
configure:
- cleanup strip fallouts
tccgen.c:
- expr_cond(): remove an exotic optimization that eventually
got fixed to do the contrary by a gv(RC_InT)
- pop_local_syms(): remove some args
- init_putv() : use write##le functions to avoid cross-compiler
unaligned access
- __bt_init(): remove unused param 'mode'
libtcc.c:
Fix unaligned load/store from magic3
tccgen.c:
For packed struct allways use single byte code
If field does not start at at align check it
Align stack correctly with vla
I have implemented the -ftest-coverage option. It works a bit different
from the gcc version. It output .tcov text file which looks almost the
same as a gcov file after a executable/so file is run.
Add lib/tcov.c file
Modify Makefiles to compile/install it
Add -ftest-coverage option in tcc.c/tcc.h/tcc-doc.texi
Add code to tccelf.c/tccgen.c/tccpe.c
Add gen_increment_tcov to tcc.h/*gen.c
unrelated changes:
Add sigemptyset in tccrun.c
Fix riscv64-gen.c tok_alloc label size
for floats (currently only). On x86_64 uses built-in fp
constants (in libtcc1.c) to avoid multiple anonymous
instances.
Also: win32/i386: use __alloca for big struct stack store
- use new function int tok_alloc_const(const char*);
- change alloca86.S to preserve EDX
tccelf.c: fix a warning with 'roinf_use'
Using "-0.0 - x" still isn't enough if x is a NaN, so bite the bullet
and implement sign-bit flipping via memory. (It's usually not too bad,
the -0.0-x method also uses memory for the floating point constant).
This way is at least shorter than implementing a new top-level operation
for all backends (a negate) that would be unary.
moved target_machine defines to the <target>-gen.c files.
Also:
- c2str.c moved into conftest.c
- tccdefs.h ; defined(__TINYC__) && !defined(_LOCORE) removed
(in tinycc __TINYC__ is always defined and _LO... is never.)
- stddef.h : too many #ifdefs, removed
- tccgen.c:stabs: support win32 long doubles aka doubles.
- win32: math.h/tcc_libm.h: fix pointer mismatch in modfl
- tccpp.c: increment include_stack_ptr after the file was
actually found otherwise it would print
"in file included from <itself>: file not found..."
netbsd does not allow text relocations in text segment.
tcc.h:
- Add data_ro_section
- Fix typo rela.plt
tccelf.c:
- Add data_ro_section
- Make bounds_section/lbounds_section rw
- Add GNU_RELRO section for data_ro_section/bounds_section/lbounds_section
- Fix relocation for __dso_handle in atexit()
tccgen.c:
- Use data_ro_section
x86_64-gen.c:
- Use R_X86_64_PC32 instead of R_X86_64_64 for bounds checking
tests/Makefile, tests/tests2/Makefile
- Enable dll tests for netbsd
This implements support for FreeBSD on aarch64
This partial implements support on FreeBSD(32). This still needs fixing
i386_gen.c because small structures on this target are passed in registers.
Add aligned 16 to __int128_t for FreeBSD
Support __i386__ on FreeBSD/NetBSD
Fix testcase 115 on FreeBSD/NetBSD
Disable testcase 116 on *BSD* because TLS_FUNC/TLS_VAR not set in bcheck.c
Remove FreeBSD/FreeBSD_kernel code from tccelf.c
tcc_enter/exit_state() are meant exclusively to protect
the tcc_compile() and its sub-functions in tccpp.c,
tccgen.c, tccasm.c and xxx-gen.c.
Other files that are part of libtcc simply must not use global
variables.
- riscv64/last_hi: move to TCCState
from 72250bece2
- tccrun.c: Using a fixed address would not work anyway
("tcc -run tcc.c -run ..." for example)
from baacb0f52a
- tests/Makefile: support for a platform doesn't make sense if
it doesn't pass our basic tests.
from 591feda103
Also:
- tccgen: cleanup "duplicate member" (only 2 passes,
avoids additional TokenSym field)
from 170be79a42
Check duplicate struct/union member names
tcc.h: Add cnt field in TokenSym
tccgen.c: New function check_fields to find duplicate member names.
This avoids quadratic behavior and can be used for large structs.
- tccpe.c: commit "tidy support for helper function" created
STT_NOTYPE symbols and hence relied on ad-hoc detection which
didn't work for x86_64 (as reported by Christian Jullien)
- tccgen.c: However to be more safe the helper symbols are
now made STT_FUNC anyway (via new VT_ASM_FUNC).
Also:
- tcc.h: minor reorder
- riscv64-*, arm64-*, tccmacho.c: avoid some gcc format-warnings
(mingw-gcc complains about "%llx" being "unknown conversion",
although it does work since Vista or so)
tcc.h, tccgen.c: Introduce Sym *external_helper_sym(int v);
to create an external reference with no specific type. This
avoids type conflicts if the symbol is used from C too.
the other files: use it.
Tcc considered function ptrs with different return types to be
compatible which disallowed some otherwise valid operations like:
`_Generic(foo, int(*)():0, void(*)(void):1)`
which would fail to compile with a error message of "type match twice"
This changed also required longjump's return type to be void and
munmap's to be int to be compatible with standard headers.
- tcc.h: msvc doesn't grok __func__ (reverts previous commit)
- tccgen.c: fortify tcc against bogus code:
- n[sizeof({3;})]; // statement expression outside of function
- f(){"123"4}; // tokens with values following each other
(also, add "type defaults to int" warning for variables)
- tccpe.c: removed a check that caused BSS symbols not to be
exported. Whatever that check was meant to prevent.
- win32/build-tcc.bat: cmd.exe sometimes doesn't grok '-' in labels
- Revert "libtcc: no need to undef"
This reverts commit 2b7aa2a1e1.
- Revert "tcc.h libtcc.c: remove unused defines"
This reverts commit 985d963745.
The point of these "unused defines" is to be unused, that is
to remind people not to use malloc but please to "use_tcc_malloc",
instead.
Fixes potential writes past the allocated space with mostly
illegal flex array initializers. (60_errors_and_warnings.c
:test_var_array)
In exchange suspicious precautions such as section_reserve
or checks with sec->data_allocated were removed. (There is
an hard check 'init_assert()' for now but it's meant to be
just temporary)
Also, instead of filling holes, always memset(0) structures
& arrays on stack. Sometimes more efficient, sometimes isn't.
At least we can omit putting null initializers.
About array range inititializers: Reparsing tokens has a
small problem with sideeffects, for example
int c = 0, dd[] = { [0 ... 1] = ++c, [2 ... 3] = ++c };
Also, instead of 'squeeze_multi_relocs()', delete pre-existing
relocations in advance. This works even if secondary initializers
don't even have relocations, as with
[0 ... 7] = &stuff,
[4] = NULL
Also, in tcc.h: new macro "tcc_internal_error()"
While MacOS doesn't natively support the alias attribute, let's support
it with TCC anyway. This means we need to make a decision if the
string in the alias attribute is decorated or not due to the implicit
underscore on MacOS. To make life easier we decide that it's the C name,
i.e. without underscore, and so TCC needs to emit alias names with
underscore handling.
Irrespective of that the test case needs to deal with the underscore
itself for __asm__ renaming which is always requiring the assembler name.
The init range with symbols did only init the first value.
The relocation for all other symbols was missing.
Also see testcase.
tccgen.c:
- New function get_init_string
- Use macro processing in decl_designator for each init string
- Use get_init_string in decl_initializer_alloc
tccelf.c:
- Fix insertion sort in squeeze_multi_relocs
tests/tests2/90_struct-init.c:
- Add test case test_init_ranges
tccgen.c:
- Fix 'tcc -b conftest.s'
- Add offset during bound checking for struct return
lib/bcheck.c:
- Check overlap when reusing vla/alloca
arm-gen.c:
arm64-gen.c:
riscv64-gen.c:
lib/alloca86-bt.S:
- add space for vla/alloca during bound checking
tests/tests2/Makefile:
tests/tests2/121_struct_return:
tests/tests2/122_vla_reuse:
- New test cases with bound checking enabled to test vla and struct return
commit 2a0167a merged alias and asm symbol renaming, but broke
semantics of aliases, see testcase. Basically the difference between
the two is that an asm rename doesn't generate a new symbol, i.e. with
int foo __asm__("bar");
all source reference to 'foo' will be to 'bar', nothing of the name
'foo' will remain in the object file, and for instance reference to
'foo' from other compilation units won't be resolved to this one.
Aliases OTOH create an additional symbol. With:
void target (void) { return; }
void afunc (void) __attribute__((alias("target")));
reference to 'afunc' will remain 'afunc' in the object file. It will
generate two symbols, 'afunc' and 'target' referring to the same entity.
This difference matters if other compilation units make references to
'afunc'.
A side requirement of this is that for alias to work that the target
symbol needs to be defined in the same unit. For TCC we even require a
stricter variant: it must be defined before the alias is created.
Now, with this I merely re-instated the old flow of events before above
commit. It didn't seem useful anymore to place both names in the
asm_label member of attributes, and the asm_label member of Sym now
again only needs the hold the __asm__ rename.
It also follows that tcc_predefs.h can't make use of attribute alias to
e.g. map __builtin_memcpy to __bound_memcpy (simply because the latter
isn't defined in all units), but rather must use __asm__ renaming, which
in turn means that the underscore handling needs to be done by hand.
The code:
struct bf_SS {unsigned int bit:1,bits31:31; };
void func(void) {
struct bf_SS bf_finit = { .bit = 1 };
}
will not init bits31 to 0.
tccgen.c:
- check_bf: New function to check if bitfield is present in struct/union
- decl_initializer: Call check_bf and set value to 0 is bitfield found
tests/tcctest.c:
- Add struct bitfield test code
reverts commit
310e3b428c
(more info there)
now functions check for
sign bit in float.
now hopefully this patch will
cover entirety of areas it might affect
reproduce bug:
$ ./configure --cc=gcc
$ make
$ make install
(OK)
run a test:
extern int printf(const char *str, ...);
int main()
{
int t2 = (int)(-1.847759065f * 4096);
printf("%d\n", t2);
}
$ tcc test.c
$ ./a.out
$ -7568
(OK)
(self compiled now)
$ ./configure --cc=tcc
$ make
$ make install
(OK)
$ tcc test.c
$ ./a.out
$ 7568
(WRONG!!!)
why:
gcc does not have intristics for
uint to long double conversion
therefore it does cast implicitly, so
the sign bit is preserved, but this does
not happen when __fixunsxfdi is called
because tcc was bootstrapped.
solution:
force cast to int64 and preserve the
sign bit.
side effects:
not found.
This allows for example this scenario:
- A dll to be linked with is specified in file.c, where file.c
and the dll exist in the same directory:
#pragma comment(lib, "txml")
#pragma comment(option, "-L{f}")
- tcc is called to run file.c from other, varying directories:
$ tcc -run some/dir/file.c <args...>
Note that tcc replaces {f} by the currently compiled file's
directory ('some/dir' in this example).
Also:
- tccgen.c: fix last commit for gen_cast.
Please respect some conventions:
- tests2 filenames don't end with '..._test'
- tests2 tests are meant to produce some output
- the output should be somehow informative, not just
"error" or "dummy". Because other people would want to
know where it fails if it does.
- tests2 tests should work with both GCC and TCC, except
if there are specifc reasons (like testing tcc-only
feature such as bounds checking)
- tests2 tests should never crash or abort. Because that
would cause gui dialogs to pop up on windows, and because
other people would not know where it fails if it does.
- tests2 tests should be somehow specific, in general.
(rather than just collections of random stuff)
- in general, do not use 'long' if you mean 'larger than int'
Because it isn't on many platforms.
- use four (4) spaces for block indention. Do not insert
tab characters in files if possible.
Also:
- tccgen.c:gen_cast() simplify last fix.
