The return value of statement expressions might refer to local
symbols, so those can't be popped. The old error message always
was just a band-aid, and since disabling it for pointer types it
wasn't effective anyway. It also never considered that also the
vtop->sym member might have referred to such symbols (see the
testcase with the local static, that used to segfault).
For fixing this (can be seen better with valgrind and SYM_DEBUG)
simply leave local symbols of stmt exprs on the stack.
But like GCC do warn about changes in signedness. The latter
leads to some changes in gen_assign_cast to not also warn about
unsigned* = int*
(where GCC warns, but only with extra warnings).
For
union U { struct {int a,b}; int c; };
union U u = {{ 1, 2, }};
The unnamed first member of union U needs to actually exist in the
structure so initializer parsing isn't confused about the double braces.
That means also the a and b members must be part of _that_, not of
union U directly. Which in turn means we need to do a bit more work
for field lookup.
See the testcase extension for more things that need to work.
Remove dead code and variables. Properly check for unions when
skipping fields in initializers. Make tests2/*.expect depend
on the .c files so they are automatically rebuilt when the latter
change.
E.g. "struct { struct S s; int a;} = { others, 42 };"
if 'others' is also a 'struct S'. Also when the value is a
compound literal. See added testcases.
Start reimplementing the whole initializer handling to be
conforming to ISO C. This patch just reimplements current
functionality to prepare for further changes, all tests pass.
This snippet is valid:
void foo(void);
... foo + 42 ...
the function designator is converted to pointer to function
implicitely. gen_op didn't do that and bailed out.
This must compile:
typedef int arrtype1[];
arrtype1 sinit19 = {1};
arrtype1 sinit20 = {2,3};
and generate two arrays of one resp. two elements. Before the fix
the determined size of the first array was encoded in the type
directly, so sinit20 couldn't be parsed anymore (because arrtype1
was thought to be only one element long).
Given this code:
struct __attribute__((...)) Name {...};
TCC was eating "Name", hence generating an anonymous struct.
It also didn't apply any packed attributes to the parsed
members. Both fixed. The testcase also contains a case
that isn't yet handled by TCC (under a BROKEN #define).
add_elf_sym is a confusing name because it is not clear what the
function does compared to put_elf_sym. As a matter of fact, put_elf_sym
also adds a symbol in a symbol table. Besides, "add_elf_sym" fails to
convey that the function can be used to update a symbol (for instance
its value). "set_elf_sym" seems like a more appropriate name: it will
set a symbol to a given set of properties (value, size, etc.) and create
a new one if non exist for that name as one would expect.
With the last improvements to lexpand it's now harmful
to use on native 64bit platforms when not necessary. For gv_dup
it's not necessary there. It can still be used with really
transforming a 64bit value into two 32bit ones.
Previously, long longs were 'lexpand'ed into two registers
always.
Now, it expands
- constants into two constants (lo-part, hi-part)
- variables into two lvalues with offset+4 for the hi-part.
This makes long long operations look a bit nicer.
Also: don't apply i386 'inc/dec' optimization if carry
generation is wanted.
gen_cast() failed to truncate long long's if they
were unsigned, which was causing mess on the vstack.
There was a similar bug here
tccgen: 32bits: fix PTR +/- long long
ed15cddacd
Both were not visible until this patch
tccgen: arm/i386: save_reg_upstack
b691585785
I'd still assume that this patch is correct per se.
Also:
- remove 2x !nocode_wanted (we are already under a general
"else if (!nocode_wanted)" clause above).
__GNUC__ nowadays as macro seems to mean the "GNU C dialect"
rather than the compiler itself. See also
http://gcc.gnu.org/ml/gcc/2008-07/msg00026.html
This patch will probably cause problems of various kinds but
maybe we should try nonetheless.
Previously in order to perform a ll+ll operation tcc
was trying to 'lexpand' PTR in gen_opl which did
not work well. The case:
int printf(const char *, ...);
char t[] = "012345678";
int main(void)
{
char *data = t;
unsigned long long r = 4;
unsigned a = 5;
unsigned long long b = 12;
*(unsigned*)(data + r) += a - b;
printf("data %s\n", data);
return 0;
}
The back end functions gen_op(comparison) and gtst() might allocate
registers so case_reg should be left on the value stack while they
are called and set again afterwards.
This bug fix was first applied as ff3f9aa (20 Feb 2015), but the fix
was reverted by fc0fc6a (21 Sep 2016, "switch: collect case ranges
first, then generate code"). Here the fix is updated for the new code.
Also:
- regenerate all tests/pp/*.expect with gcc
- test "insert one space" feature
- test "0x1E-1" in asm mode case
- PARSE_FLAG_SPACES: ignore \f\v\r better
- tcc.h: move some things
We need to preserve the type of the pointer to the structure, f.ex.
when a global structure is returned.
This is not a perfect solution. Registers loaded in the first iteration
might be overwritten in a following iteration as the register is no
longer on vtop. This is not a problem for ARM32 as gfunc_sret returns
a maximum of 1 in the integer case.
Makefile :
- do not 'uninstall' peoples /usr/local/doc entirely
libtcc.c :
- MEM_DEBUG : IDE-friendly output "file:line: ..."
- always ELF for objects
tccgen.c :
- fix memory leak in new switch code
- move static 'in_sizeof' out of function
profiling :
- define 'static' to empty
resolve_sym() :
- replace by dlsym()
win32/64: fix R_XXX_RELATIVE fixme
- was fixed for i386 already in
8e4d64be2f
- do not -Lsystemdir if compiling to .o
tccgen.c:gv() when loading long long from lvalue, before
was saving all registers which caused problems in the arm
function call register parameter preparation, as with
void foo(long long y, int x);
int main(void)
{
unsigned int *xx[1], x;
unsigned long long *yy[1], y;
foo(**yy, **xx);
return 0;
}
Now only the modified register is saved if necessary,
as in this case where it is used to store the result
of the post-inc:
long long *p, v, **pp;
v = 1;
p = &v;
p[0]++;
printf("another long long spill test : %lld\n", *p);
i386-gen.c :
- found a similar problem with TOK_UMULL caused by the
vstack juggle in tccgen:gen_opl()
(bug seen only when using EBX as 4th register)
"make test" crashes without that "save_regs()".
This partially reverts
commit 49d3118621.
Found another solution: In a 2nd pass Just look if
any of the argument registers has been saved again,
and restore if so.
This was causing assembler bugs in a tcc compiled by itself
at i386-asm.c:352 when ExprValue.v was changed to uint64_t:
if (op->e.v == (int8_t)op->e.v)
op->type |= OP_IM8S;
A general test case:
#include <stdio.h>
int main(int argc, char **argv)
{
long long ll = 4000;
int i = (char)ll;
printf("%d\n", i);
return 0;
}
Output was "4000", now "-96".
Also: add "asmtest2" as asmtest with tcc compiled by itself
On 2016-08-11 09:24 +0100, Balazs Kezes wrote:
> I think it's just that that copy_params() never restores the spilled
> registers. Maybe it needs some extra code at the end to see if any
> parameters have been spilled to stack and then restore them?
I've spent some time on this and I've found an alternative solution.
Although I'm not entirely sure about it but I've attached a patch
nevertheless.
And while poking at that I've found another problem affecting the
unsigned long long division on arm and I've attached a patch for that
too.
More details in the patches themselves. Please review and consider them
for merging! Thank you!
--
Balazs
[PATCH 1/2] Fix slow unsigned long long division on ARM
The macro AEABI_UXDIVMOD expands to this bit:
#define AEABI_UXDIVMOD(name,type, rettype, typemacro) \
...
while (num >= den) { \
...
while ((q << 1) * den <= num && q * den <= typemacro ## _MAX / 2) \
q <<= 1; \
...
With the current ULONG_MAX version the inner loop goes only until 4
billion so the outer loop will progress very slowly if num is large.
With ULLONG_MAX the inner loop works as expected. The current version is
probably a result of a typo.
The following bash snippet demonstrates the bug:
$ uname -a
Linux eper 4.4.16-2-ARCH #1 Wed Aug 10 20:03:13 MDT 2016 armv6l GNU/Linux
$ cat div.c
int printf(const char *, ...);
int main(void) {
unsigned long long num, denom;
num = 12345678901234567ULL;
denom = 7;
printf("%lld\n", num / denom);
return 0;
}
$ time tcc -run div.c
1763668414462081
real 0m16.291s
user 0m15.860s
sys 0m0.020s
[PATCH 2/2] Fix long long dereference during argument passing on ARMv6
For some reason the code spills the register to the stack. copy_params
in arm-gen.c doesn't expect this so bad code is generated. It's not
entirely clear why the saving part is necessary. It was added in commit
59c35638 with the comment "fixed long long code gen bug" with no further
clarification. Given that tcctest.c passes without this, maybe it's no
longer needed? Let's remove it.
Also add a new testcase just for this. After I've managed to make the
tests compile on a raspberry pi, I get the following diff without this
patch:
--- test.ref 2016-08-22 22:12:43.380000000 +0100
+++ test.out3 2016-08-22 22:12:49.990000000 +0100
@@ -499,7 +499,7 @@
2
1 0 1 0
4886718345
-shift: 9 9 9312
+shift: 291 291 291
shiftc: 36 36 2328
shiftc: 0 0 9998683865088
manyarg_test:
More discussion on this thread:
https://lists.nongnu.org/archive/html/tinycc-devel/2016-08/msg00004.html
- "utf8 in identifiers"
from 936819a1b9
- CValue: remove member str.data_allocated
- make tiny allocator private to tccpp
- allocate macro_stack objects on heap
because otherwise it could crash after error/setjmp
in preprocess_delete():end_macro()
- mov "TinyAlloc" defs to tccpp.c
- define_push: take int* str again
fixes 5c35ba66c5
Implementation was consistent within tcc but incompatible
with the ABI (for example library functions vprintf etc)
Also:
- tccpp.c/get_tok_str() : avoid "unknown format "%llu" warning
- x86_64_gen.c/gen_vla_alloc() : fix vstack leak
The case below previously was causing an assertion failure
in the target specific generator.
It probably is not incorrect not to allow this even if
gcc does.
struct S { long b; };
void f(struct S *x)
{
struct S y[1] = { *x };
}
The check for structs was too late and on amd64 and aarch64 could
lead to accepting and then asserting with code like:
struct S {...} s;
char *c = (char*)0x10 - s;
... for fast redeclaration checks
Also, check function parameters too:
void foo(int a) { int a; ... }
Also, try to fix struct/union/enum's on different scopes:
{ struct xxx { int x; };
{ struct xxx { int y; }; ... }}
and some (probably not all) combination with incomplete
declarations "struct xxx;"
Replaces 2bfedb1867
and 07d896c8e5
Fixes cf95ac399c
A constant expression removed from the loop.
If subroutine have 50000+ local variables, then currently
compilation of such code takes obly 15 sec. Was 2 min.
gcc-4.1.2 compiles such code in 7 sec. pcc -- 3.44 min.
A test generator:
#include <stdio.h>
int main() {
puts("#include <stdio.h>"); puts("int main()"); puts("{");
for (int i = 0; i < 50000; ++i) printf("int X%d = 1;\n", i);
for (int i = 0; i < 50000; ++i) puts("scanf(\"%d\", &X0);");
puts("}");
return 0;
}
don't catch redefinition for local vars. With this option on
tcc accepts the following code:
int main()
{
int a = 0;
long a = 0;
}
But if you shure there is no problem with your local variables,
then a compilation speed can be improved if you have a lots of
the local variables (50000+)
From gcc docs: "You may also specify attributes between the enum, struct or union tag and the name of the type rather than after the closing brace."
Adds `82_attribs_position.c` in `tests/tests2`
the check on incomplete struct/union/enum types was too early,
disallowing mixed specifiers and qualifiers. Simply rely on
the size (->c) field for that. See testcases.
A CString used to be copied into a token string, which is an int array.
On a 64-bit architecture the pointers were misaligned, so ASan gave
lots of warnings. On a 64-bit architecture that required memory
accesses to be correctly aligned it would not work at all.
The CString is now included in CValue instead.
Some test cases:
#define SE ({ switch (0) { } 0; })
// Should give error:
int x = SE;
void f(void) { static int x = SE; }
void f(void) { enum e { a = SE }; }
void f(void) { switch (0) { case SE: break; } }
// Correct:
int f(void) { return SE; }
int f(void) { return sizeof(SE); }
- avoid memory allocation by using its (int) token number
- avoid additional function parameter by using Attribute
Also: fix some strange looking error messages
In a case like
typedef int T[1];
const T x;
we must make a copy of the typedef type so that we can add the type
qualifiers to it.
The following code used to give
error: incompatible types for redefinition of 'f'
typedef int T[1];
void f(const int [1]);
void f(const T);
don't crash
a test program:
================
typedef struct X { int len; } X;
#define init(s,len) s.len = len;
int main(void) {
X myX;
init(myX,10);
return 0;
}
================
After a patch:
error: field name expected
a test program:
========
typedef struct X { int len; } X;
int main(void) {
X myX;
myX.10 = 10;
return 0;
}
========
Error message before a patch:
error: ';' expected (got "(null)")
After a patch:
error: field name expected
* Documentation is now in "docs".
* Source code is now in "src".
* Misc. fixes here and there so that everything still works.
I think I got everything in this commit, but I only tested this
on Linux (Make) and Windows (CMake), so I might've messed
something up on other platforms...
Jsut for testing. It works for me (don't break anything)
Small fixes for x86_64-gen.c in "tccpp: fix issues, add tests"
are dropped in flavor of this patch.
Pip Cet:
Okay, here's a first patch that fixes the problem (but I've found
another bug, yet unfixed, in the process), though it's not
particularly pretty code (I tried hard to keep the changes to the
minimum necessary). If we decide to actually get rid of VT_QLONG and
VT_QFLOAT (please, can we?), there are some further simplifications in
tccgen.c that might offset some of the cost of this patch.
The idea is that an integer is no longer enough to describe how an
argument is stored in registers. There are a number of possibilities
(none, integer register, two integer registers, float register, two
float registers, integer register plus float register, float register
plus integer register), and instead of enumerating them I've
introduced a RegArgs type that stores the offsets for each of our
registers (for the other architectures, it's simply an int specifying
the number of registers). If someone strongly prefers an enum, we
could do that instead, but I believe this is a place where keeping
things general is worth it, because this way it should be doable to
add SSE or AVX support.
There is one line in the patch that looks suspicious:
} else {
addr = (addr + align - 1) & -align;
param_addr = addr;
addr += size;
- sse_param_index += reg_count;
}
break;
However, this actually fixes one half of a bug we have when calling a
function with eight double arguments "interrupted" by a two-double
structure after the seventh double argument:
f(double,double,double,double,double,double,double,struct { double
x,y; },double);
In this case, the last argument should be passed in %xmm7. This patch
fixes the problem in gfunc_prolog, but not the corresponding problem
in gfunc_call, which I'll try tackling next.
* fix some macro expansion issues
* add some pp tests in tests/pp
* improved tcc -E output for better diff'ability
* remove -dD feature (quirky code, exotic feature,
didn't work well)
Based partially on ideas / researches from PipCet
Some issues remain with VA_ARGS macros (if used in a
rather tricky way).
Also, to keep it simple, the pp doesn't automtically
add any extra spaces to separate tokens which otherwise
would form wrong tokens if re-read from tcc -E output
(such as '+' '=') GCC does that, other compilers don't.
* cleanups
- #line 01 "file" / # 01 "file" processing
- #pragma comment(lib,"foo")
- tcc -E: forward some pragmas to output (pack, comment(lib))
- fix macro parameter list parsing mess from
a3fc543459a715d7143d
(some coffee might help, next time ;)
- introduce TOK_PPSTR - to have character constants as
written in the file (similar to TOK_PPNUM)
- allow '\' appear in macros
- new functions begin/end_macro to:
- fix switching macro levels during expansion
- allow unget_tok to unget more than one tok
- slight speedup by using bitflags in isidnum_table
Also:
- x86_64.c : fix decl after statements
- i386-gen,c : fix a vstack leak with VLA on windows
- configure/Makefile : build on windows (MSYS) was broken
- tcc_warning: fflush stderr to keep output order (win32)
Author: Philip <pipcet@gmail.com>
Our VLA code can be made a lot simpler (simple enough for
even me to understand it) by giving up on the optimization idea, which
is very tempting. There's a patch to do that attached, feel free to
test and commit it if you like. (It passes all the tests, at least
I think this code only affects the ARM EABI target, and only when
returning small structures that might be unaligned. However, it was both
leaking vstack entries and failing to achieve what I think is its
purpose, to ensure the sret argument would be aligned properly. Both
issues fixed.
This patch disables the optimization of saving stack pointers lazily,
which didn't fully take into account that control flow might not reach
the stack-saving instructions. I've decided to leave in the extra calls
to vla_sp_save() in case anyone wants to restore this optimization.
Tests added and enabled.
There are two remaining bugs: VLA variables can be modified, and jumping
into the scope of a declared VLA will cause a segfault rather than a
compiler error. Both of these do not affect correct C code, but should
be fixed at some point. Once VLA variables have been made properly
immutable, we can share them with the saved stack pointer and save stack
and instructions.
- pop_macro incorrect with initially undefined macro
- horrible implementation (tcc_open_bf)
- crashes eventually (abuse of Sym->prev_tok)
- the (unrelated) asm_label part is the opposite of a fix
(Despite of its name this variable has nothing to do with
the built-in assembler)
This reverts commit 0c8447db79.
* give warning if pragma is unknown for tcc
* don't free asm_label in sym_free(),
it's a job of the asm_free_labels().
The above pragmas are used in the mingw headers.
Thise pragmas are implemented in gcc-4.5+ and current
clang.
This is for a case when no '{' is used in the initialization code.
An option name is -fold-struct-init-code. A linux 2.4.26 can't
find initrd when compiled with a new algorithm.
- a warning: unnamed struct/union that defines no instances
- allow a nested named struct declaration w/o identifier
only when option -fms-extensions is used
On Linux 32: sizeof(long)=32 == sizeof(void *)=32
on Linux 64: sizeof(long)=64 == sizeof(void *)=64
on Windows 64: sizeof(long)=32 != sizeof(void *)=64
The following check in tccgen.c is removed
if (nocode_wanted)
tcc_error("statement expression in global scope");
This check is introduced in commit 5bcc3eed7b and breaks compilation
of the linux 2.4.26 kernel.
int i = i++ causes a segfault because of missing guard. Looking
recursively at all backend functions called from middle end several more
guard appeared to be missing.
The common code to move a returned structure packed into
registers into memory on the caller side didn't take the
register size into account when allocating local storage,
so sometimes that lead to stack overwrites (e.g. in 73_arm64.c),
on x86_64. This fixes it by generally making gfunc_sret also return
the register size.
__clear_cache is defined in lib-arm64.c with a single call to
__arm64_clear_cache, which is the real built-in function and is
turned into inline assembler by gen_clear_cache in arm64-gen.c
More precisely, treat (0 << x) and so on as constant expressions, but
not if const_wanted as we do not want to allow "case (x*0):", ...
Do not optimise (0 / x) and (0 % x) here as x might be zero, though
for an architecture that does not generate an exception for division
by zero the back end might choose to optimise those.
a test program:
struct {
int a[2], b[2];
} cases[] = {
{ ((int)0), (((int)0)) },
((int)0), (((int)0)) /* error: ',' expected (got ")") */
};
int main() { return 0; }
This commit allow to skip ')' in the decl_initializer() and to see ','
A test program:
//////////////
int main()
{
void *p = ({ 0 ; ((void *)1); });
}
/////////////
Porblem is introduced in a commit a80acab: Display error on statement expressions with complex return type
This error is exposed when compiling a linux 2.4.26. tcc 0.9.23 can sucessfully compile
this version of the linux.
Current tcc don't understand an initialization of the empty struct
This problem was found trying to compile a linux kernel 2.4.26
which can be compiled by tcc 0.9.23
A test program:
////////////////////
// ./tcc -c test_3.c
// test_3.c:31: error: too many field init
#undef __GNUC__
#undef __GNUC_MINOR__
#define __GNUC__ 2
#define __GNUC_MINOR__ 95
typedef struct { } rwlock_t;
struct fs_struct {
int count;
rwlock_t lock;
int umask;
};
#define INIT_FS { \
1, \
RW_LOCK_UNLOCKED, \
0022, \
}
#if (__GNUC__ > 2 || __GNUC_MINOR__ > 91)
typedef struct { } rwlock_t;
#define RW_LOCK_UNLOCKED (rwlock_t) { }
#else
typedef struct { int gcc_is_buggy; } rwlock_t;
#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
#endif
static struct fs_struct init_fs = INIT_FS;
// static struct fs_struct init_fs = { { (1) }, (rwlock_t) { 0 }, 0022, };
// ^ with this all Ok
// static struct fs_struct init_fs = { { (1) }, (rwlock_t) { }, 0022, };
// ^ current tcc don't understand, but tcc 0.9.23 can
int main()
{
return 0;
}
////////////////////
A regression is detected after a patch 69fdb57edd
////////////////////
// A test for patch 69fdb57edd
// Author: grischka <grischka>
// Date: Wed Jun 17 02:09:07 2009 +0200
// unions: initzialize only one field
// struct {
// union {
// int a,b;
// };
// int c;
// } sss = { 1,2 };
// This had previously assigned 1,2 to a,b and 0 to c which is wrong.
//
// Expected: sss.a=1 sss.b=1 sss.c=2
int main()
{
struct {
union {
int a,b;
};
int c;
} sss = { 1, 2 };
printf ("sss.a=%d sss.b=%d sss.c=%d\n", sss.a, sss.b, sss.c);
return 0;
}
////////////////////
A regression was found trying to compile a linux kernel 2.4.26
which can be compiled by tcc 0.9.23
///////////////////
#include <stdio.h>
// test for a bug:
// compiler don't understand am extern array of structs
// $ tcc test_1.c
// test_1.c:8: error: unknown struct/union/enum
extern struct FILE std_files[4];
int main()
{
return 0;
}
//////////////////
tcc-current
/* enum/struct/union declaration. u is either VT_ENUM or VT_STRUCT */
static void struct_decl(CType *type, int u, int tdef)
...
if (tok != '{') {
v = tok;
next();
/* struct already defined ? return it */
if (v < TOK_IDENT)
expect("struct/union/enum name");
s = struct_find(v);
if (s) {
if (s->type.t != a)
tcc_error("invalid type");
goto do_decl;
} else if (tok >= TOK_IDENT && !tdef)
tcc_error("unknown struct/union/enum");
} else {
v = anon_sym++;
}
tcc-0.9.23 which don't have such error
/* enum/struct/union declaration. u is either VT_ENUM or VT_STRUCT */
static void struct_decl(CType *type, int u)
....
if (tok != '{') {
v = tok;
next();
/* struct already defined ? return it */
if (v < TOK_IDENT)
expect("struct/union/enum name");
s = struct_find(v);
if (s) {
if (s->type.t != a)
error("invalid type");
goto do_decl;
}
} else {
v = anon_sym++;
}
libtcc.c: Add greloca, a generalisation of greloc that takes an addend.
tcc.h: Add greloca and put_elf_reloca.
tccelf.c: Add put_elf_reloca, a generalisation of put_elf_reloc.
tccgen.c: On x86_64, use greloca instead of greloc in init_putv.
The back end functions gen_op(comparison) and gtst() might allocate
registers so case_reg should be left on the value stack while they
are called and set again afterwards.
This for example suppresses string constants such as with
int main()
{
return sizeof "foo";
}
Actually, setting
nocode_wanted = 1;
in libtcc.c for the initial global level seemed wrong, since
obviously "nocode_wanted" means code as any side effects, also
such as string constants.
This reverts a part of 2de1b2d14c
(documented as "Some in-between fixes" in Changelog)
This adds parsing of (GCC compatible) visibility attribute
in order to mark selected global symbols as hidden. The generated
.o files contain hidden symbols already, the TCC linker doesn't
yet do the right thing.
*** UNCONDITIONALLY ***
Esp. sihce tinycc winapi headers are not as complete as people might
expect this can otherwise lead to obscure problems that are difficult
to debug.
(Originally 'warn_implicit_function_declaration' was set to 1
always for windows but someone must have deleted that line)
This was going wrong (case TOK_LAND in unary: computed labels)
- vset(&s->type, VT_CONST | VT_SYM, 0);
- vtop->sym = s;
This does the right thing and is shorter:
+ vpushsym(&s->type, s);
Test case was:
int main(int argc, char **argv)
{
int x;
static void *label_return = &&lbl_return;
printf("label_return = %p\n", label_return);
goto *label_return; //<<<<< here segfault on linux X86_64 without the memset on vset
printf("unreachable\n");
lbl_return:
return 0;
}
Also::
- Rename "void* CValue.ptr" to more usable "addr_t ptr_offset"
and start to use it in obvious cases.
- use __attribute__ ((noreturn)) only with gnu compiler
- Revert CValue memsets ("After several days searching ...")
commit 4bc83ac393
Doesn't mean that the vsetX/vpush thingy isn't brittle and
there still might be bugs as to differences in how the CValue
union was set and is then interpreted later on.
However the big memset hammer was just too slow (-3% overall).
For program manipulating argv or arge as pointer with construct such as:
(while *argv++) {
do_something_with_argv;
}
it is necessary to have argv and arge inside a region. This patch create
regions argv and arge) if main is declared with those parameters.
I found the problem it was because CValue stack variables have rubish as it inital values
and assigning to a member that is smaller than the big union item and trying to
recover it later as a different member gives bak garbage.
ST_FUNC void vset(TCCState* tcc_state, CType *type, int r, int v)
{
CValue cval;
memset(&cval, 0, sizeof(CValue));
cval.i = v; //,<<<<<<<<<<< here is the main bug that mix with garbage
vsetc(tcc_state, type, r, &cval);
}
/* store a value or an expression directly in global data or in local array */
static void init_putv(TCCState* tcc_state, CType *type, Section *sec, unsigned long c,
int v, int expr_type)
{
...
case VT_PTR:
if (tcc_state->tccgen_vtop->r & VT_SYM) {
greloc(tcc_state, sec, tcc_state->tccgen_vtop->sym, c, R_DATA_PTR);
}
//<<< on the next line is where we try to get the assigned value to cvalue.i as cvalue.ull
*(addr_t *)ptr |= (tcc_state->tccgen_vtop->c.ull & bit_mask) << bit_pos;
break;
Also this patch makes vla tests pass on linux 32 bits
When checking for exact compatibility between types (such as in
__builtin_types_compatible_p) consider the case of default signedness to
be incompatible with both of the explicit signedness for char. That is,
char is incompatible with signed char *and* unsigned char, no matter
what the default signedness for char is.
negate(x) is subtract(-0,x), not subtract(+0,x), which makes
a difference with signed zeros. Also +x was expressed as x+0,
in order for the integer promotions to happen, but also mangles signed
zeros, so just don't do that with floating types.
Applying 64bit relocs assumes that the CVal is initialized to zero
for the whole 64bit. Consolidate this a bit, at the same time
zeroing the .ull member more consistently when needed. Fixes segfault
on x86_64-linux using global vars in tcctest.c.
Michael Matz