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.
tccelf.c:
- Check if symbol is in data section and UNDEF. Then generate new
relocation and let dynamic linker solve it.
tests/tests2/42_function_pointer.c:
- Add new test code
lib/bt-exe.c:
- call __bound_init before sigset_exception_handler because sigaction
is redirected.
tests/tests2/Makefile:
- run testcase 114 on macos again
Note:
I removed the test that used sin()
function because it makes no sense
to use that there and besides I could
not get the test to work because
sin requires -lm linked but for some reason
make does not compile with -lm and
I get errors like undefined symbol sin.
Coerce function should do the same thing
for the purposes of that test.
The BOUNDS_CHECKING_ON/BOUNDS_CHECKING_OFF is not working for
signal/sigaction/fork. The reason is that the code stops bound checking
for the whole application. This result in wrong handling of
__bound_local_new/__bound_local_delete and malloc/calloc/realloc/free.
Consider the following code:
void tst(int n) {
int i, arr[n];
for (i = 0; i < n; i++) arr[i] = 0;
}
void *some_thread(void *dummy) {
while (running) { tst(10); tst(20); }
}
void signal_handler(int sig) { ... }
When the signal handler is called the some_thread code can be interrupted when
is just registered the arr[10] data. When the signal handler is leaved the
arr[10] is still registered and did not see the call to deregister arr[10] and
then register arr[20]. The code resumes when tst(20) is running. This results
in a bound checking error when i >= 10.
To solve the above problem I changed the bound checking code to use
tls (thread local storage) for the no_checking variable.
This also makes it now possible to redirect signal/sigaction/fork code
through the bound checking library and disable checking when a signal is
running and to correct the bounds_sem for the fork child process.
The BOUNDS_CHECKING_ON/BOUNDS_CHECKING_OFF is not needed any more for
signal/sigaction/fork. In fact I could remove them from all my applications.
The use of the tls function code slows down the code by about 10%.
So if the slowdown due to bound checking was 5. It is now 5.5 times slower.
For x86_64/i386 I also allowed to use __thread variable in bcheck.c when
compiled with gcc with:
make x86_64-libtcc1-usegcc=yes
make i386-libtcc1-usegcc=yes
This makes code run faster due to use of gcc and __thread variable.
With the __thread variable there is no 10% slowdown.
For other targets this does not work because stabs is not supported.
Changes:
lib/bcheck.c:
- Add TRY_SEM
- Add HAVE_SIGNAL/HAVE_SIGACTION/HAVE_FORK/HAVE_TLS_FUNC/HAVE_TLS_VAR
- HAVE_SIGNAL: redirect signal() call if set.
- HAVE_SIGACTION: redirect sigaction() call if set.
- HAVE_FORK: redirect fork() call if set.
- HAVE_TLS_FUNC: If target has tls function calls.
- HAVE_TLS_VAR: If target has __thread tls support.
- Replace all no_checking refecrences to NO_CHECKING_SET/NO_CHECKING_GET macros
tcc-doc.texi:
- Remove examples for signal/sigaction/fork code.
- Add some explanation for signal/sigaction/fork code.
- Add documentaion for __bounds_checking().
tccelf.c:
- Add support for SHF_TLS
tests/tests2/114_bound_signal.c:
- Remove BOUNDS_CHECKING_ON/BOUNDS_CHECKING_OFF
- Add code to trigger failure when tls is not working.
x86_64-link.c:
- Add support for R_X86_64_TLSGD/R_X86_64_TLSLD/R_X86_64_DTPOFF32/R_X86_64_TPOFF32
i386-link.c:
- Add support for R_386_TLS_GD/R_386_TLS_LDM/R_386_TLS_LDO_32/R_386_TLS_LE
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.
Providing both run-time and compile-time control for bounds
checking as an user interface appears unnecessary and confusing.
Also:
- replace 'bound_...' by 'bounds_...' for consistency
- tcc-doc: put related info into one place and cleanup
The __bounds_checking(x) function is still missing explanation.
(I.e. what happens if the accumulated value drops below zero.)
tcctok.h:
- Add CONFIG_TCC_BCHECK arround TOK_NO_BOUND_CHECK1/TOK_NO_BOUND_CHECK2
tccgen.c:
- Add CONFIG_TCC_BCHECK arround TOK_NO_BOUND_CHECK1/TOK_NO_BOUND_CHECK2
- Undo alias definition in tccpp.c when function bound checking if off
tests/tests2/114_bound_signal.c:
- Test alias undo
- fix sleep problem
i386-gen.c:
- Fix large stack size alloca code.
The returned value of alloca was not used corectly.
libtcc.c:
- Use __SIZE_TYPE__ for __builtin_offsetof
tccpp.c:
- Fix __MAYBE_REDIR and abort builtins.
tests/tests2/Makefile
- Run 117_gcc_test also with bound checking enabled
This found the above problems.
tccgen.c:
- cleanup __builtin_... stuff
- merge __attribute((alias("sym"))) with __asm__("sym")
Now one cannot have both, however for alias underscores are
added if enabled. For __asm__ they aren't.
tccpp.c:
- extend tcc_predefs accordingly. Was generated with
'cd tests/misc && tcc -run c2str.c tcc_predef.h tcc_predefs'
xxx-gen.c:
- move bcheck setjmp test to tccgen.c:gbound_args()
i386-gen.c:
- create win32 compatible stack space for big structures
tcctest.c:
- some cleanup + nicer output
tested on win32/64 to pass the tests when enabled
- libtcc.c :
let tcc define __leading_underscore if enabled
tcc_add_symbol() : add _ automatically
- tccelf.c : remove tcc_get_symbol_err(), find_c_sym()
currently symbol length is limited to 256 in several
places, so we can use a fixed local buffer for now as well.
- win32/lib/crtinit.c : new file for init/fini
- lib/*.S, tests7* : use __leading_underscore
- bt-log.c: this file wont work relibaly if compiled with gcc
- configure/Makefile : cleanup, really use CC_NAME
- tccasm.c : remove C99 construct that MSVC doesn't compile
- arm-gen.c, x86_64-gen.c, riscv64-gen.c, tccmacho.c : ditto
- arm64-gen.c: commit 383acf8eff wrote:
"Instead of a cast, it would be better to pass the exact type."
It is true that there are better solutions but it is not
passing the exact type (I think).
- tcctest.c: revert "fix cast test for clang" 03646ad46f
this obviously wants to test non-portable conversions
- 114_bound_signal.test: clock_nanosleep is too new for older
linuxes, just use sleep() instead
via some heavy-handed hackery in the ASM symbol handling in case
C symbols get a leading underscore (but ASM symbols do not).
But this is now like clang and GCC on Darwin work: asm symbols are
undecorated, C symbols get a _ prepended, so to connect both some
trickery is involved for the ASM symbols that don't have a _ prepended.
They must be included in the C symbol table (because that's what we use
to lookup also ASM labels), but they also must not disturb the normal
C symbol (which don't have the _ prepended), so they need some mangling.
A bit unsatisfying, but well. So, add asm-c-connect-test to the working
ones for Darwin as well.
* instead of /usr/include use the current SDK path as system
include directory (/usr/include is empty with current tools)
(this also removes the need to add these paths in individual
Makefiles)
* define _DARWIN_C_SOURCE in tcc.h to get the full set of decls
from system headers (e.g. vsnprintf), similar to _GNU_SOURCE
(and don't define _ANSI_SOURCE in the main Makefile anymore)
* tests/tests2/Makefile: remove the -w flag, it's added when necessary
in the rules generating the .expect files
* <malloc.h> isn't as portable as <stdlib.h>
* skip 113_btdll.c on Darwin
* replace [...]\+ with [...]\{1,\} in the sed regex (basic REs
have no + even some sed(1) accept it as \+, but bounds _are_ part
of POSIX BREs)
It might have advantages in cases if tcc/libtcc does not
depend on extern files.
Also:
- apply "stray \\ ..." check to macros only. For files it
was already checked. Add positive test.
Checked on:
- i386/x86_64 (linux/windows)
- arm/arm64 (rapberry pi)
- riscv64 (simulator)
Not tested for arm softfloat because raspberry pi does not support it.
Modifications:
Makefile:
add arm-asm.c to arm64_FILES
add riscv64-asm.c (new file) to riscv64_FILES
lib/Makefile:
add fetch_and_add_arm.o(new file) to ARM_O
add fetch_and_add_arm64.o(new file) to ARM64_O
add fetch_and_add_riscv64.o(new file) to RISCV64_O
add $(BCHECK_O) to OBJ-arm/OBJ-arm64/OBJ-riscv64
tcc.h:
Enable CONFIG_TCC_BCHECK for arm32/arm64/riscv64
Add arm-asm.c, riscv64-asm.c
tcctok.h:
for arm use memmove4 instead of memcpy4
for arm use memmove8 instead of memcpy8
tccgen.c:
put_extern_sym2: for arm check memcpy/memmove/memset/memmove4/memmove8
only use alloca for i386/x86_64
for arm use memmove4 instead of memcpy4
for arm use memmove8 instead of memcpy8
fix builtin_frame_address/builtin_return_address for arm/riscv64
tccrun.c:
Add riscv64 support
fix rt_getcontext/rt_get_caller_pc for arm
tccelf.c:
tcc_load_dll: Print filename for bad architecture
libtcc.c:
add arm-asm.c/riscv64-asm.c
tcc-doc.texi:
Add arm, arm64, riscv64 support for bound checking
lib/bcheck.c:
add __bound___aeabi_memcpy/__bound___aeabi_memmove
__bound___aeabi_memmove4/__bound___aeabi_memmove8
__bound___aeabi_memset for arm
call fetch_and_add_arm/fetch_and_add_arm64/fetch_and_add_riscv64
__bound_init: Fix type for start/end/ad
__bound_malloc/__bound_memalign/__bound_realloc/__bound_calloc: Use size + 1
arm-gen.c:
add bound checking code like i386/x86_64
assign_regs: only malloc if nb_args != 0
gen_opi/gen_opf: Fix reload problems
arm-link.c:
relocate_plt: Fix address calculating
arm64-gen.c:
add bound checking code like i386/x86_64
load/store: remove VT_BOUNDED from sv->r
arm64_hfa_aux/arm64_hfa_aux: Fix array code
gfunc_prolog: only malloc if n != 0
arm64-link.c:
code_reloc/gotplt_entry_type/relocate: add R_AARCH64_LDST64_ABS_LO12_NC
relocate: Use addXXle instead of writeXXle
riscv64-gen.c:
add bound checking code like i386/x86_64
add NB_ASM_REGS/CONFIG_TCC_ASM
riscv64-link.c:
relocate: Use addXXle instead of writeXXle
i386-gen.c/x86_64-gen.c
gen_bounds_epilog: Fix code (unrelated)
tests/Makefile:
add $(BTESTS) for arm/arm64/riscv64
tests/tests2/Makefile:
Use 85 only on i386/x86_64 because of asm code
Use 113 only on i386/x86_64 because of DLL code
Add 112/114/115/116 for arm/arm64/riscv64
Fix FILTER (failed on riscv64)
tests/boundtest.c:
Only use alloca for i386/x86_64
an enum must be compatible with one or more integer type,
so adjust the test accordingly. That means the following
redeclarations should work:
enum e6 { E1 = -1, E0 };
void f3(enum e6);
void f3(int); // should work as int and e6 are compatible
while the following should not:
void f4(enum e6 e);
void f4(unsigned e); // should error as unsigned and e6 are incompatible
they were emitted too early, in particular also in macro
substitution which might turn out to not be stray in case it's
further stringified. Check in next() instead. Add two testcases
that an error is still emitted for obvious top-level baskslashes,
and that stringifying such a thing works.
tcctok.h:
- Add __bound_setjmp/setjmp/_setjmp/longjmp
tccgen.c:
- redirect setjmp/longjmp to bcheck.c code
i386-gen.c/x86_64-gen.c
- Change func_bound_alloca_used into func_bound_add_epilog
- Set func_bound_add_epilog also when setjmp is called
bcheck.c:
- Add __bound_setjmp/__bound_longjmp
- __bound_local_delete: remove setjmp if used in function
- __bound_exit: clear setjmp list and print statistic
- make malloc_redir more readable (unrelated)
New testcases:
- 115_bound_setjmp
- 116_bound_setjmp2
Merge function attributes with those given given for the
prototype, also handle post-decl appearance such as
void func() __attribute__((noreturn))
{
}
Also, some test fixes (unrelated).
as there's overlap between handling types for binary and ternay
operations. Factor this into a single routine (combine_types).
This uses the structure that gen_op was following, and expr_cond
was using as well in the past, which I find easier to reconvene
with the standard language. But it reuses the new functions for
diagnostics to improve (a little) on what GCC or clang produce :)
On windows. there is no long double really IOW it is the
same as double. However setting the VT_LONG flag in
combination with VT_DOUBLE allows to keep track of the
original type for the purpose of '_Generic() or more
accurate type warnings.
Fix static assert to support literal string instead of just printing
the sring of the current token as it use to be
so we can now use _Static_assert(0, "0" "1") which will print
__FILE__ __LINE__ error: 01
so that it also is called from the precedence parser. This
is complicated by the fact that something needs to be done before
the second operand is parsed in a single pass compiler, so it
doesn't quite fit into expr_infix itself. It turns out the smallest
code changes result when expr_landor remains separate. But it can
be tidied a bit.
- tests2/113_btdll.c: test handling multiple stabs infos
Also:
- libtcc.c: remove _ISOC99_SOURCE pre-defines. It is causing
strange warnings such as 'strdup not declared'
- i386/x86_64-gen.c cleanup bounds_pro/epilog. This discards
the extra code for main's argv. If needed, __argv might be
processed instead.
- tccgen.c:block(): reduce stackspace usage. For example with
code like "if (..) ... else if (..) ... else if (..)... "
considerable numbers of nested block() calls may occur.
Before that most stack space used when compiling itself was
for libtcc.c:tcc_set_linker().
Now it's rather this construct at tccpp.c:2765: in next_nomacro1():
if (!((isidnum_table[c - CH_EOF] & (IS_ID|IS_NUM))
|| c == '.'
|| ((c == '+' || c == '-')
...
the strcat checker first checks dest for overlap, then src.
If the padding byte between b[] and the pad[] arrays happens to be zero
the dest check would have succeeded and the src test failed. If that
padding byte would be zero the dest check would trigger first.
As we can't influence the padding byte (only the b[] and pad[] arrays)
it was random if the dest or src checks triggered.
This makes it reliably trigger the dest check first.
This makes it possible to get backtraces with executables
(including DLLs/SOs) like we had it already with -g -run.
Option -b includes -bt, and -bt includes -g.
- new file lib/bt-exe.c: used to link rt_printline and the
exception handler from tccrun.c into executables/DLLs.
- new file lib/bt-log.c: provides a function that may be
called from user code to print out a backtrace with a
message (currently for i386/x86_64 only):
int (*tcc_backtrace)(const char *fmt, ...);
As an extra hack, if 'fmt' is prefixed like "^file.c^..."
then the backtrace will skip calls from within 'file.c'.
- new file lib/bt-dll.c: used on win32 to link the backtrace
and bcheck functions with the main module at runtime
- bcheck.c: now uses the tcc_backtrace function from above
- tccgen.c: minor cleanups
- tccelf.c: stab sections get SHF_ALLOC for easy access.
Also in relocate_section(): 64bit relocations for stabs
in DLLs cannot work. To find DLL addresses, the DLL base
is added manually in tccrun.c via rc.prog_base instead.
- tccpe.c: there are some changes to allow merging sections,
used to merge .finit_array into .data in the first place.
- tccpp.c: tcc -run now #defines __TCC_RUN__
also: refactor a line in tal_realloc that was incompatible
with bcheck
- tcctest.c: fixed a problem with r12 which tcc cannot preserve
as well as gcc does.
- tests2/112_backtrace.c: test the feature and the bcheck test18
that previously was in boundtest.c
we were emitting error messages for something like
'static int i = 2 || 1/0', even though the exception would be in
the unevaluated part. This doesn't destroy const-ness, so we must
accept it. This requires splitting the nocode_wanted values a bit more,
so that nocode_wanted due to const_wanted can be differentiated from
nocode_wanted due to non-evaluation.
The bounds checking code has now enabled gen_bounded_ptr_add tests.
This makes the code slower but finds more errors.
I had to correct some things in tcc to make it work.
- Fixed off by one in lib/bcheck.c
- Corrected tccelf.c sym_versions.
- Disabled USE_TAL when using bounds checking.
- Fixed cstr_printf va_start.
- Fixed tests/tests2/46_grep.c off by one error.
- Updated gen_bounded_ptr_add in x86_64-gen.c
- Fixed x86_64-link.c pointer diff.
For gen_vla_alloc now always use alloca call when bounds checking.
Added line/filename in %rax before bound calls to find location of error.
This fixes the issue
int main() { extern char *x; }
void main1() { extern char *x; }
t2.c:5: error: incompatible types for redefinition of 'x'
(reported by Giovanni Mascellani 2019/07/16)
the uninitialized cumofs was leading to random sizes for
the memset when initializing local structures, potentially
leading to segfaults from it. Only a problem with GNU
designated initializers, which we didn't test very well.
See testcase.
A more automatic approach to code suppression (aka. nocode_wanted)
The simple rules are:
- Clear 'nocode_wanted' at (im/explicit) label IF it was used
- Set 'nocode_wanted' after unconditional jumps
Also in order to test this then I did add the "function might
return no value" warning, and then to make that work again I
did add the __attribute__((noreturn)).
Also moved the look ahead label check into the type parser
to gain a little speed.
Example:
int a = 1;
void f(void)
{
int a = 2;
{
extern int a; // = 1 !!
....
To get this (more) correctly there is a new function to copy
syms between local to global stacks.
Also, this patch changes the meaning of VT_EXTERN back
to the simpler and IMO more useful notion of
DECLARED but not (yet) DEFINED.
and that for both variables and functions. That is, VT_EXTERN
in tcc doesn't have to do with the keyword 'extern' necessarily.
Also this patch does allow
int x[];
as alias for
extern int x[];
(as do gcc and msvc)
... which IMO are:
1) files don't need a _test suffix because all files in
the directory are tests ;)
2) we test the BEHAVIOR of the program, rather than its
binary bit contents.
Ok, but nobody said a test can't use two files ;)
(where the 104+_ construct is meant to prevent the file
from being picked up by the makefile as a test on its own).
Previously test 104 used a combination of *nix tools and system() calls
to emulate a `sh` script, which required split code paths for windows
due to different shell and different absolute path representation.
Also, it used a hardcoded tcc binary path, didn't set locale for sort.
Now the tools are used from a `sh` script which the program generates
and invokes, tmp files are at CWD and no conversion is required, tcc
path is taken from Makefile (exported), and `sort` uses LC_ALL=C.
- add tests for standard conformant inline functions
- implement it
The old tinycc failed to provide a conforming implementation
of non-static inlines. It would expose external symbols where it
shouldn't and hide them where it should expose them.
This commit provides a hopefully comprehensive test suite
for how things should be done. The .expect file can be obtained
by compiling the example c file (embedded in the test)
with a conforming compiler such as gcc, clang or icc and then
printing the exported symbols (e.g., with nm+awk+sort).
(The implementation currently reserves two new VT_ flags.
If anyone can provide an implementation without reserving
two extra flags, please replace mine.)
anonymous struct members were somewhat broken as the testcase
demonstrates. The reason is the jumping through hoops to fiddle
with the offsets I once introduced to avoid having to track
a cumulative offset. That's now not necessary anymore and actively
harmful, doing the obvious thing is now better.
see testcase, when the inner array dimension of multi-dimensional
VLAs isn't given TCC was generating invalid vstack accesses.
Those are actually invalid, so just diagnose them.
see testcases. A local 'extern int i' declaration needs to
refer to the global declaration, not to a local one it might
be shadowing. Doesn't seem to happen in the wild very often as
this was broken forever.
in presence of invalid source code we can't rely on the
next token to determine if we have or haven't already parsed
an initializer element, we really have to track it in some separate
state; it's a flag, so merge it with the other two we have (size_only
and first). Also add some syntax checks for situations which
formerly lead to vstack leaks, see the added testcases.
sometimes abstract decls in parameter lists left the returned name
uninitialized potentially leading to segfaults, like in
int f(int ()) {
return 0;
}
Deal with this.
like on 'enum myenum { L = -1 } L;'. It's a bit tedious as
there are two paths (for global vs local symbols), and because
the scope and enum_val share same storage.
