read() is allowed to short-read, and return less bytes then requested.
The caller must restart read() when this happens (and they want more
bytes).
This patch is still buggy, because errors are not always checked.
Still, less buggy than before.
symbols are local when defined and referred to from the executable.
Also, we need to relocate the .got section when this is a static link
(our static linking effectively generates code as if this were a dynamic
link with PLT and GOT, and then emulates the runtime loader).
misc fixes including:
- tcc.c: fix "tcc -vv" for libtcc1.a on win32/PE
- tccelf.c: fix a crash when GOT has no relocs (witn -nostdlib)
- tccelf.c: fix stab linkage for zero n_strx
- tccgen.c: fix stdcall decoration for array parameters
int __stdcall func(char buf[10]) is _func@4 (was _func@12)
- tccgen.c: fix static variables with nocode/nodata_wanted
see tests2/96_nodata_wanted.c
- tccrun.c: align sections using sh_addralign (for reliable function_alignment)
- tests2/Makefile sort 100 after 99
- win32/include/sys/stat.h fix _stat and _wstat
- x86_64-gen.c: win64/gfunc_call: fix a bug with xmmN register args
previously overwrote valid other xmmN registers eventually
This is supposed to fix a bug where libtcc eventually was trying to
compile libtcc1.a as C source code.
Anyway, there is now only two functions that refer to s->filetype,
tcc_add_file() and tcc_add_library().
In prepare_dynamic_rel() on non x86 targets the count++ statements
appear before any case label and are therefore dead code. This triggers
build failure when building with -Werror. This patch adds an extra guard
around all the x86 case labels and their associated action, leaving just
the default case label for non x86 targets which builds fine.
Origin: vendor
Forwarded: no
Last-Updated: 2018-02-24
for a final link we shouldn't emit relocation sections that are applied
already. For now we need to emit ALLOCed .rel sections as they contain
dynamic relocs, they should be put into their own (new) section instead.
tccgen.c:
- fix ldouble asm hack
- fix a VLA problem on Win64 (also x86_64-gen.c)
- patch_type(): make sure that no symbol ever changes
from global to static
tcc.c:
- tcc -vv: print libtcc1.a path also on win32
tccpe.c, tcctools.c:
- use unix LF mode to for .def output files (that is for
creating reproducible output trees)
Makefile:
- suppress some warnings when makeinfo is missing
- call 'which install' only on win32
tests/Makefile:
- change PATH only on WINNT systems (i.e. not if cross-compiling
on linux for win32)
- asm-c-connect.test: slim output and do diff
tccrun.c tccpe.c *-link.c:
- integrate former 'pe_relocate_rva()' into normal relocation
This also fixes linkage of the unwind data on WIN64 for -run
(reported by Janus Lynggaard Thorborg)
tccasm.c, tests/tcctest.c:
- fix dot (sym_index of -1 crashed in put_elf_reloc)
- massage .set a bit (see test)
other:
- #define SECTION_ABS removed
- ST_DATA Section *strtab_section: removed
- put_extern_sym2(): take int section number
Conflicts:
tccelf.c
tccpe.c
Conflicts:
tccelf.c
This is supposed to make compilation and linking with
multiple source files (tcc f1.c f2.S ...) behave just
the same as linking object files.
tccgen.c:put_extern_sym2():
- use put_elf_sym to enter new symbols unconditionally
tccelf.c:
- save section state before compilation
- disable symbol hashing during compilation
- merge symbols and update relocations after compilation
tccpe.c:
- re-create s1->uw_sym for each compilation (because it
may change)
for this we have to create also asm symbols as VT_STATIC initially
except if there's an indication that it should be global (.globl
or undefined at end of unit). For this to work we need to
be able to globalize symbols after they were local and enter them
into the ELF hash tables, and also adjust the symbols that were
potentially already used in relocs when they were still local.
The easiest is to do a proper symbol resolution step also in multi-file
mode, for regular symbols (the non-dynamic ones, i.e. not from shared
libs).
* removed asm_label stack
* removed asm_free_labels() post-processing
* using "impossible C type" for asm labels (VT_ASM)
* tccgen.c:update_storage(): use it to refresh symbol attributes
* tccelf.c:find_elf_sym(): ignore STB_LOCAL symbols
* tccgen.c:unary(): asm symbols are supposed to be undeclared in C
This makes the asm symbols use the same members as the C symbols
for global decls, e.g. using the ELF symbol to hold offset and
section. That allows us to use only one symbol table for C and
asm symbols and to get rid of hacks to synch between them.
We still need some special handling for symbols that come purely
from asm sources.
win32/Makefile ("for cygwin") removed
- On cygwin, the normal ./configure && make can be used with either
cygwin's "GCC for Win32 Toolchain"
./configure --cross-prefix=i686-w64-mingw32-
or with an existing tcc:
./configure --cc=<old-tccdir>/tcc.exe
tcctest.c:
- exclude test_high_clobbers() on _WIN64 (does not work)
tests2/95_bitfield.c:
- use 'signed char' for ARM (where default 'char' is unsigned)
tests:
- remove -I "expr" diff option to allow tests with
busybox-diff.
libtcc.c, tcc.c:
- removed -iwithprefix option. It is supposed to be
combined with -iprefix which we don't have either.
tccgen.c:
- fix assignments and return of 'void', as in
void f() {
void *p, *q;
*p = *q:
return *p;
}
This appears to be allowed but should do nothing.
tcc.h, libtcc.c, tccpp.c:
- Revert "Introduce VIP sysinclude paths which are always searched first"
This reverts commit 1d5e386b0a.
The patch was giving tcc's system includes priority over -I which
is not how it should be.
tccelf.c:
- add DT_TEXTREL tag only if text relocations are actually
used (which is likely not the case on x86_64)
- prepare_dynamic_rel(): avoid relocation of unresolved
(weak) symbols
tccrun.c:
- for HAVE_SELINUX, use two mappings to the same (real) file.
(it was so once except the RX mapping wasn't used at all).
tccpe.c:
- fix relocation constant used for x86_64 (by Andrei E. Warentin)
- #ifndef _WIN32 do "chmod 755 ..." to get runnable exes on cygwin.
tccasm.c:
- keep forward asm labels static, otherwise they will endup
in dynsym eventually.
configure, Makefile:
- mingw32: respect ./configure options --bindir --docdir --libdir
- allow overriding tcc when building libtcc1.a and libtcc.def with
make XTCC=<tcc program to use>
- use $(wildcard ...) for install to allow installing just
a cross compiler for example
make cross-arm
make install
- use name <target>-libtcc1.a
build-tcc.bat:
- add options: -clean, -b bindir
Currently tcc doesn't have a compile-time config indicating that the target
is freebsd, and as a result, the tcc binary adds freebsh stuff to elf headers
if the compile-time (of tcc) *host* is freebsd.
Test also that the target is not PE while generating an elf header.
This still likely fails (but untested) when tcc targets other non-freebsd
systems on a freebsd system, but for now fix it only when targetting windows.
any dyn symbols. The if( !s1->static_link ) prevents tcc from
crashing when buiding a program linked to dietlibc.
The section header should not contain the number of local symbols when
the sh_size is null. This makes the header compliant and IDA will not
issue any warnings when an executable is disassembled.
- 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
Mark TCCState parameter as unused in tcc_undefine_symbol(), tcc_add_symbol(),
tcc_print_stats(), asm_get_local_label_name(), use_section1(), tccpp_delete(),
tcc_tool_ar(), tcc_tool_impdef(), and tcc_tool_cross().
Also mark it unused in tcc_add_bcheck() unless CONFIG_TCC_BCHECK.
Remove it entirely in ld_next().
some newer systems have debug sections compressed by default, which
includes those in the crt[1in].o startup files. These can't simply
be concatenated like all others (which leads to invalid section contents
ultimately making gdb fail) but need special handling.
Instead of that special handling (decompressing, which in turn requires
linking against zlib) let's just ignore such sections, even though that
means to also ignore all other debug sections from that particular input
file. Our own generated files of course don't have the problem.
introduce common_section (SHN_COMMON), factorize some handling
in decl_initializer_alloc, add section_add and use it to factorize
some code that allocates stuff in sections (at the same time also fixing
harmless bugs re section alignment), use init_putv to emit float consts
into .data from gv() (fixing an XXX).
Don't emit useless section headers and also sort them in allocated
order. Doesn't change behaviour except makes the resulting files
a tiny bit smaller (though at the expense of some very tiny compile
time and code size increase of tcc itself; not 100% it's worth it).
The O(xxx) stuff in i386-asm.c had me scratching my head. Extracting
the macro and trying it out in a separate program doesn't give
me any warnings, so I'm confused about what could be going on there.
Any cast will make things happy. I used a uint64_t to catch actual
cases of overflow, which will still cause a -Wconstant-conversion
warning.
Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com>
since configure supports only native configuration
a file 'cross-tcc.mak' needs to be created manually.
It is included in the Makefile if present.
# ----------------------------------------------------
# Example config-cross.mak:
#
# windows -> i386-linux cross-compiler
# (it expects the linux files in <prefix>/i386-linux)
ROOT-i386 = {B}/i386-linux
CRT-i386 = $(ROOT-i386)/usr/lib
LIB-i386 = $(ROOT-i386)/lib:$(ROOT-i386)/usr/lib
INC-i386 = {B}/lib/include:$(ROOT-i386)/usr/include
DEF-i386 += -D__linux__
# ----------------------------------------------------
Also:
- use libtcc1-<target>.a instead of directories
- add dummy arm assembler
- remove include dependencies from armeabi.c/lib-arm64.c
- tccelf/ld_add_file: add SYSROOT (when defined) to absolute
filenames coming from ld-scripts
Today by accident i had to deal with linker problems of some
software and found an issue that mentioned DT_RUNPATH, which
mentioned that DT_RPATH is legacy and searched for
$LD_LIBRARY_PATH, whereas the newer DT_RUNPATH is searched
thereafter. Completely unencrypted! Well. For what's it worth,
i for one am astonished because of course i want to override
$LD_LIBRARY_PATH, but it surely has its merites, smart people came
to the conclusion, did they.
The attached diff below seems to be sufficient to support
DT_RUNPATH instead of DT_RPATH with tcc(1). But i have no insight
in what --enable-new-dtags is supposed to change in addition, so
i wonder.
Ciao!
--steffen
libtcc.c | 2 ++
tcc-doc.texi | 4 ++++
tcc.h | 1 +
tccelf.c | 3 ++-
4 files changed, 9 insertions(+), 1 deletion(-)
- tccgen.c/tcc.h: allow function declaration after use:
int f() { return g(); }
int g() { return 1; }
may be a warning but not an error
see also 76cb1144ef
- tccgen.c: redundant code related to inline functions removed
(functions used anywhere have sym->c set automatically)
- tccgen.c: make 32bit llop non-equal test portable
(probably not on C67)
- dynarray_add: change prototype to possibly avoid aliasing
problems or at least warnings
- lib/alloca*.S: ".section .note.GNU-stack,"",%progbits" removed
(has no effect)
- tccpe: set SizeOfCode field (for correct upx decompression)
- libtcc.c: fixed alternative -run invocation
tcc "-run -lxxx ..." file.c
(meant to load the library after file).
Also supported now:
tcc files ... options ... -run @ arguments ...
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.
- generate and use SYM@PLT for plt addresses
- get rid of patch_dynsym_undef hack (no idea what it did on FreeBSD)
- use sym_attrs instead of symtab_to_dynsym
- special case for function pointers into .so on i386
- libtcc_test: test tcc_add_symbol with data object
- move target specicic code to *-link.c files
- add R_XXX_RELATIVE (needed for PE)
MSVC does not support array designator so cannot compile source using
relocs_info. This commit replace the relocs_info array into a set of
functions, each returning the value given by a given field of the struct
reloc_info.
i386 target does not have PC relative loads. Its ABI therefore require
ebx register to points to the GOT when executing a PLT entry. This means
that PLT entry cannot be used transparently, the compiler needs to
expect execution of a PLT entry to be able to use one, that is a PLT
entry should only be created if the relocation explicitely asks for it
(eg. R_386_PLT32).
This patch creates a new target macro PCRELATIVE_DLLPLT to indicate
whether a target can do a PC relative load in PLT entry when building a
dynamic library. Executable do not normally pose a problem because they
are loaded at a fixed address and thus the absolute address of GOT can
be used.
Note that in such a case, if the compiler does not use a PLT aware
relocation for external access then the code relocation will fall on the
dynamic loader since there is no PLT entry to relocate too.
Static relocation of functions in dynamic libraries must use the PLT
entry as the target. Before this commit, it used to be done in 2 parts
for ARM, with the offset of the PLT entry from the beginning of the PLT
being put in the relocated place in build_got_entries () and then the
address of the PLT being added in relocate_section.
This led to code dealing with reading the offset of a bl instruction in
build_got_entries. Furthermore, the addition of the address of the start
of the PLT was done based on the relocation type which does not convey
whether a PLT entry should be used to reach the symbol.
This commit moves the decision to use the PLT as the target in
relocate_section, therefore having the instruction aware code contained
to the target-specific bit of that function (in <target>-link.c).
Note that relocate_syms is *not* the right place to do this because two
different relocations for the same symbol can make different decision.
This is the case in tcc -run mode where the static and dynamic
relocation are done by tcc.
Storing the PLT entry address in the symbol's st_value field and relying
on the specific relocation type being used for dynamic relocation would
work but the PLT entry address would then appear in the static symbol
table (symtab). This would also make the static symbol table entry
differ from the dynamic symbol table entry.
Change alloc_sym_attr into get_sym_attr and add a parameter to control
whether to allocate a new symattr structure or return NULL if symbol is
not found;
Currently GOT/PLT creation happens in two locations depending on whether
the GOT/PLT [entry] is required by the symbol or the relocation:
- bind_exe_dynsym for relocations to undefined symbol
- build_got_entries/put_got_entry for relocations that require a GOT/PLT
entry
This commit consolidate GOT/PLT creation in build_got_entries by
reducing bind_exe_dynsym's job to create a dynamic symbol for undefined
symbols. build_got_entries then invoke put_got_entry if the symbol being
relocated is undefined or the relocation asks for a PLT or GOT [entry].
put_got_entry is also modified to only export a symbol in the dynamic
symbol table when we are in the case of PLT/GOT [entry] required by the
relocation (since undefined symbol are already exported by
bind_exe_dynsym).
Currently we always build a GOT when we recognize a relocation in
build_got_entries even if the relocation does not require one. In the
same spirit, when the relocation does require one we always create a GOT
entry even if not entry is necessary. This patch restricts the creation
of a GOT and a GOT entry to relocations that needs it, ie:
- do not create a GOT if relocation is not related to GOT and symbol is
not UNDEF
- do not create a GOT entry if relocation only relates to beginning of
GOT
On ARM targets, the jump to ld.so resolution routine is done in PLT0 by
loading the offset to the GOT found in PLT+16 and from there loading the
address in GOT+8 and jumping to it.
Currently tcc starts the first regular PLT entry at PLT+16 which thus
does not contain the offset to the GOT. This commit fixes that.
Note that calls via PLT still worked nonetheless because of some missing
dynamic tag which makes ld.so behaves as if RTLD_BIND_NOW was specified
in the environment for all executable created by tcc.
