The call to build_got can cause symtab_section->data to be reallocated
(build_got -> add_elf_sym -> put_elf_sym -> section_ptr_add ->
section_realloc -> tcc_realloc). This is not obvious on a cursory
inspection, but fortunately Valgrind spotted it immediately.
Are there other, similar bugs that Valgrind did not detect?
* 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...
* 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)
Prior to this commit TinyCC was exporting symbols defined in programs
only when they resolve an undefined symbol of a library. However, the
expected behavior (see --export-dynamic in GNU ld manpage) is that all
symbols used by libraries and defined by a program should be exported in
dynsym section. This is because symbol resolution search first in
program and then in libraries, thus allowing program symbol to interpose
symbol defined in a library.
Usage example: tcc -xc ex5.cgi
From a gcc docs:
You can specify the input language explicitly with the -x option:
-x language
Specify explicitly the language for the following input files
(rather than letting the compiler choose a default based on the file
name suffix). This option applies to all following input files until
the next -x option. Possible values for language are:
c c-header c-cpp-output
c++ c++-header c++-cpp-output
objective-c objective-c-header objective-c-cpp-output
objective-c++ objective-c++-header objective-c++-cpp-output
assembler assembler-with-cpp
ada
f77 f77-cpp-input f95 f95-cpp-input
java
-x none
Turn off any specification of a language, so that subsequent files
are handled according to their file name suffixes (as they are if -x
has not been used at all)
* define targetos=Windows when --enable-tcc32-mingw, --enable-cygwin, ...
* use TARGETOS insteed HOST_OS when selecting PROGS
* use "$(tccdir)" insteed $(tccdir) on install (spaces in path)
* install tcc.exe too
* produce bcheck.o when cross-compiling too (lib/Makefile)
* force bcheck.o linking by compiling inside tcc_set_output_type()
a dummy program with local array. Otherwise bcheck.o may be not linked.
* replace %xz format specifier with %p in bcheck (don't supported on
Windows)
* call a __bound_init when __bound_ptr_add, __bound_ptr_indir,
__bound_new_region, __bound_delete_region called.
This is because a __bound_init inside ".init" section is not called
on Windows for unknown reason.
* print on stderr a message when an illegal pointer is returned:
there is no segmentation violation on Windows for a program
compiled with "tcc -b"
* remove "C:" subdir on clean if $HOST_OS = "Linux"
* default CFLAGS="-Wall -g -O0" insteed CFLAGS="-Wall -g -O2"
to speed up compilation and more precise debugging.
tcc w/o -g option generate an executable file which format
is not recognized by binutils. It is like stripped one but
binutils don't think so. Solution: generate not stripped
file which can be correctly stripped by external utils.
may be there is a need to handle a -s option and call
a sstrip/strip program to do a job.
- care about __attribute__ redefinition in the system headers
- an invalid pointer must be returned when (addr >= e->size),
and not (addr > e->size)
A test program:
#include <stdio.h>
#include <stdlib.h>
int main ()
{
int v[10];
fprintf(stderr, "&v[0] = %p\n", &v[0]);
fprintf(stderr, "&v[10] = %p\n", &v[10]);
exit(1);
return 0;
}
// tcc -b test.c
The output before a patch:
&v[0] = 0xbf929d8c
&v[10] = 0xbf929db4
The output after a patch:
&v[0] = 0xbff6e33c
&v[10] = 0xfffffffe
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
A test program (must be compiled by the above version of the tcc):
/* Tickle a bug in TinyC on 64-bit systems:
* the LSB of the top word or ARGP gets set
* for no obvious reason.
*
* Source: a legacy language interpreter which
* has a little stack / stack pointer for arguments.
*
* Output is: 0x8049620 0x10804961c
* Should be: 0x8049620 0x804961c
*/
#include <stdio.h>
#define NARGS 20000
int ARG[NARGS];
int *ARGSPACE = ARG;
int *ARGP = ARG - 1;
main() { printf("%p %p\n", ARGSPACE, ARGP); }
Don't use /usr/local/lib/tcc/libtcc1.a for i386 and x86_64
A $(tccdir)/i386 directory was used to install a libtcc1.a
but only when cross compiling. And no x86_64 directory.
And this directory location was unknown inside tccelf.c
It is a strange patch because before this commit a gdb is working well
and after this commit there is exactly the same problem on Linux:
gdb refuses to know "main"
Author: grischka <grischka>
Date: Tue Feb 5 21:18:29 2013 +0100
tccelf: fix debug section relocation
With:
tcc -g hello.c
gdb a.out
b main
gdb refused to know "main" because of broken dwarf info.
This adds some more support for properly transfering some
offsets over the different stages of a relocations life.
Still not at all psABI compliant and DSOs can't yet be generated.
But it runs the testsuite in qemu-arm64.
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.
- revert to R_X86_64_PC32 for near calls on PE
- revert to s1->section_align set to zero by default
Untested. Compared to release_0_9_26 the pe-image looks back to
normal. There are some differences in dissassembly (r10/r11 usage)
but maybe that's ok.
Same as with x86_64, disable the runtime_plt_and_got hack
for -run on arm as well. For that we need to handle several
relocations as (potentially) generating PLT slots as well.
Tested with mpfr-3.1.2 and gawk (both using --disable-shared),
there are two resp. five pre-existing problems, so no regressions.
This also works toward enabling real shared libs for arm,
but it's not there yet.
This makes us use the normal PLT/GOT codepaths also for -run,
which formerly used an on-the-side blob for the jump tables.
For x86_64 only for now, arm coming up.
These relocations are used to express a dependency on a certain
symbol (e.g. for EABIs exception handling to the
__aeabi_unwind_cpp_pr{0,1,2} routines). Just ignore them in
reloc processing.
When output is memory we applied the correct GOT offset for certain
relocations (e.g. _GOT32), but we forgot to actually fill the got
entries with the final symbol values, so unconditionally create relocs
against .got as well.
This makes it so that the first PT_LOAD segment covers
ELF and program header and .interp (contained in the same page anyway,
right before the start of the first loaded section). binutils
strip creates invalid output otherwise (which strictly is a binutils
bug, but let's be nice anyway).
This correctly resolves local references to global functions from
shared libs to their PLT slot (instead of directly to the target
symbol), so that interposition works.
This is still not 100% conforming (executables don't export symbols
that are also defined in linked shared libs, as they must), but
normal shared lib situations work.
Introduce a new attribute to check the existence of a PLT entry for a
given symbol has the presence of an entry for that symbol in the dynsym
section is not proof that a PLT entry exists.
This fixes commit dc8ea93b13.
Some symbol (such as __gmon_start__ but this one does not matter to tcc)
can have both a R_386_GOT32 and R_386_PLT32 relocation. It is thus not
enough to test if a GOT reloc was already done when deciding whether to
return early from put_got_entry.
When bound check is enabled, tcc tries to relocate a call to
__bound_init in _init. This means that relocation (in tcc_add_bcheck)
must be done after libtcc1.a (which countains __bound_init) is loaded
but before crtn.o is loaded as this finalize _init.
