In the linux kernel sources:
#ifdef __STDC__
#define SYMBOL_NAME_LABEL(X) X##:
#else
#define SYMBOL_NAME_LABEL(X) X/**/:
#endif
tcc is a STDC compiler and must handle 'X##:' case.
A new version of the MEM_DEBUG will be submitted next. This version is
not depend on the malloc_usable_size() presense in the libc and
print a places where a leaked chunks of memory was allocated.
* 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
This requires moving TOK_PLCHLDR handling, but the new logic should make
things easier even if (when?) GNU comma handling is removed.
(Somewhat confusingly, GCC no longer supports GNU commas. See
http://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html for a description
of past and current GCC behaviour.)
Fix handling of escape characters, spaces, and line feeds in macros or
macro arguments that might yet be subject to # stringification.
Should this be an -f option? I think memory usage increases only very
slightly (in particular, while line feeds, stray \s, and spaces are
preserved, comments are not), so it's probably not worth it to make it
one.
Note that macro_subst now checks for stray \s which are still left in
the input stream after macro substitution, if desired.
This patch depends on the previous patch, so if you revert that, please
revert this patch, too.
See http://lists.nongnu.org/archive/html/tinycc-devel/2015-05/msg00002.html
This adds a PARSE_FLAG_ACCEPT_STRAYS parse flag to accept stray
backslashes in the source code, and uses it for pure preprocessing.
For absolutely correct behaviour of # stringification, we need to use
this flag when parsing macro definitions and in macro arguments, as
well; this patch does not yet do so. The test case for that is something
like
#define STRINGIFY2(x) #x
#define STRINGIFY(x) STRINGIFY2(x)
STRINGIFY(\n)
which should produce "\n", not a parse error or "\\n".
See http://lists.nongnu.org/archive/html/tinycc-devel/2015-05/msg00002.html
Perhaps a better fix would be to ensure tok is set to TOK_EOF rather
than 0 at the end of a macro stream.
This partially fixes test2 of the examples given in:
http://lists.nongnu.org/archive/html/tinycc-devel/2015-05/msg00002.html
It's still failing, but at least it's not running out of memory now.
The old code had an inverted condition, so
#define a(b)## b
would be accepted while
#define a(b,c) b ## ## c
would be rejected with the confusing error message "'##' invalid at
start of macro".
Quick fix for
http://lists.nongnu.org/archive/html/tinycc-devel/2015-04/msg00160.html.
I don't fully understand the intended semantics of when file->buf_ptr[0]
is valid, but the rest of the code doesn't have any obvious spots with
the same bug.
Feel free to revert this if I'm mistaken or we need to discuss this
change further.
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.
The old code assumed that if an argument doesn't fit into the available
registers, none of the subsequent arguments do, either. But that's
wrong: passing 7 doubles, then a two-double struct, then another double
should generate code that passes the 9th argument in the 8th register
and the two-double struct on the stack. We now do so.
However, this patch does not yet fix the function calling code to do the
right thing in the same case.
The comment suggests this was meant to detect unions, but in fact it
compared f->c, the union/struct size, against f->next->c, the first
element's offset.
This affected only zero-length structs/unions with a first (zero-length)
element, as in this code:
struct u2 {
};
struct u {
struct u2 u2;
} u;
struct u f(struct u x)
{
return x;
}
However, such structures turned out to be broken anyway, as code like this
was generated for the above f:
0000000000000000 <f>:
0: 55 push %rbp
1: 48 89 e5 mov %rsp,%rbp
4: 48 81 ec 10 00 00 00 sub $0x10,%rsp
b: 66 0f d6 45 f8 movq %xmm0,-0x8(%rbp)
10: 66 0f 6e 45 f8 movd -0x8(%rbp),%xmm0
15: e9 00 00 00 00 jmpq 1a <f+0x1a>
1a: c9 leaveq
1b: c3 retq
With the x86_64 Linux ELF ABI, we're currently failing two of these
three tests, which have been disabled for now. The problem is mixed
structures such as struct { double x; char c; }, which the x86_64 ABI
specifies are to be passed/returned in one integer register and one SSE
register; our current approach, marking the structure as VT_QLONG or
VT_QFLOAT, fails in this case.
(It's possible to fix this by getting rid of VT_QLONG and VT_QFLOAT
entirely as at https://github.com/pipcet/tinycc, but the changes aren't
properly isolated at present. Anyway, there might be a less disruptive
fix.)
- 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.
I ran into an issue playing with tinycc, and tracked it down to a rather
weird assumption in the function calling code. This breaks only when
varargs and float/double arguments are combined, I think, and only when
calling GCC-generated (or non-TinyCC, at least) code. The problem is we
sometimes generate code like this:
804a468: 4c 89 d9 mov %r11,%rcx
804a46b: b8 01 00 00 00 mov $0x1,%eax
804a470: 48 8b 45 c0 mov -0x40(%rbp),%rax
804a474: 4c 8b 18 mov (%rax),%r11
804a477: 41 ff d3 callq *%r11
for a function call. Note how $eax is first set to the correct value,
then clobbered when we try to load the function pointer into R11. With
the patch, the code generated is:
804a468: 4c 89 d9 mov %r11,%rcx
804a46b: b8 01 00 00 00 mov $0x1,%eax
804a470: 4c 8b 5d c0 mov -0x40(%rbp),%r11
804a474: 4d 8b 1b mov (%r11),%r11
804a477: 41 ff d3 callq *%r11
which is correct.
This becomes an issue when get_reg(RC_INT) is modified not always to
return %rax after a save_regs(0), because then another register (%ecx,
say) is clobbered, and the function passed an invalid argument.
A rather convoluted test case that generates the above code is
included. Please note that the test will not cause a failure because
TinyCC code ignores the %rax argument, but it will cause incorrect
behavior when combined with GCC code, which might wrongly fail to save
XMM registers and cause data corruption.
Verify an immediate value fits into 32 bits before jumping to it/calling
it with a 32-bit immediate operand. Without this fix, code along the
lines of
((int (*)(const char *, ...))140244834372944LL)("hi\n");
will fail mysteriously, even if that decimal constant is the correct
address for printf.
See https://github.com/pipcet/tinycc/tree/bugfix-1
* 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.
Commit 5ce2154c ("-fdollar-in-identifiers addon", 20-04-2015) forgot
to include the test files from Daniel's patch.
Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
