Closed
Description
I've run into a regression with Clang 17, and I've bisected it to ffc1205. @gchatelet
One of the test cases from the pngquant project fails with a SIGBUS error when built with Clang 17 on ppc64le. The SIGBUS is coming from this OpenMP loop
Below is a script to build pngquant and reproduce the error. I've also attached the good and bad disassembly of the binary. Let me know what other information would help resolve this bug.
Stack Trace:
#0 0x00007ffff7b5b7fc in __kmp_init_indirect_csptr (crit=0x100455dc <gomp_critical_user_libpng[var]>, loc=0x10034cf0, gtid=<optimized out>, tag=locktag_queuing) at /root/dev/llvm-project/openmp/runtime/src/kmp_csupport.cpp:1066
#1 0x00007ffff7b5b2f4 in __kmpc_critical_with_hint (loc=0x10034cf0, global_tid=0, crit=0x100455dc <gomp_critical_user_libpng[var]>, hint=0) at /root/dev/llvm-project/openmp/runtime/src/kmp_csupport.cpp:1503
#2 0x00007ffff7b5b114 in __kmpc_critical (loc=<optimized out>, global_tid=0, crit=<optimized out>) at /root/dev/llvm-project/openmp/runtime/src/kmp_csupport.cpp:1257
#3 0x0000000010015c90 in read_image (options=0x1005de20, filename=0x7ffffffff154 "/tmp/pngquantfGwdZc/skiptest.png", using_stdin=0, input_image_p=0x7fffffffd5d0, liq_image_p=0x7fffffffd8a8, keep_input_pixels=<optimized out>, strip=<optimized out>, verbose=<optimized out>) at pngquant.c:690
#4 0x0000000010016b38 in pngquant_file_internal (filename=0x7ffffffff154 "/tmp/pngquantfGwdZc/skiptest.png", options=<optimized out>, liq=0x1005de20, outname=<optimized out>) at pngquant.c:436
#5 .omp_outlined._debug__ (options=@0x7fffffffe3e8: 0x7fffffffe0a0, .global_tid.=<optimized out>, .bound_tid.=<optimized out>, liq=<optimized out>, latest_error=<optimized out>, skipped_count=<optimized out>, error_count=<optimized out>, file_count=<optimized out>) at pngquant.c:386
#6 .omp_outlined. (.global_tid.=<optimized out>, .bound_tid.=<optimized out>, options=<optimized out>, liq=@0x7fffffffe3e0: 0x100502b0, latest_error=@0x7fffffffe108: SUCCESS, skipped_count=@0x7fffffffe110: 0, error_count=@0x7fffffffe3f0: 0, file_count=@0x7fffffffe10c: 0) at pngquant.c:352
#7 0x00007ffff7c26e64 in __kmp_invoke_microtask () at /root/dev/llvm-project/openmp/runtime/src/z_Linux_asm.S:1701
#8 0x00007ffff7b7adf8 in __kmp_invoke_task_func (gtid=0) at /root/dev/llvm-project/openmp/runtime/src/kmp_runtime.cpp:7674
#9 0x00007ffff7b706d4 in __kmp_fork_call (loc=0x10034cd8, gtid=0, call_context=<optimized out>, argc=<optimized out>, microtask=<optimized out>, invoker=0x7ffff7b7ab40 <__kmp_invoke_task_func(int)>, ap=<optimized out>) at /root/dev/llvm-project/openmp/runtime/src/kmp_runtime.cpp:2337
#10 0x00007ffff7b59268 in __kmpc_fork_call (loc=0x10034cd8, argc=6, microtask=0x10016180 <.omp_outlined.>) at /root/dev/llvm-project/openmp/runtime/src/kmp_csupport.cpp:300
#11 0x0000000010015824 in pngquant_main_internal (options=0x7fffffffe0a0, liq=0x100502b0) at pngquant.c:352
#12 main (argc=<optimized out>, argv=<optimized out>) at pngquant.c:318
[bad.s.txt](https://github.com/llvm/llvm-project/files/11456711/bad.s.txt)Script to Reproduce:
libomp_installdir=/root/dev/llvm-project/install/lib/
# dnf install libpng-devel lcms2-devel
git clone https://github.com/pornel/pngquant
git checkout 2.18.0
pushd pngquant
export CFLAGS='-O2 -flto -g'
export LDFLAGS="-Wl,-z,relro -Wl,--as-needed -Wl,-z,now -Wl,--build-id=sha1 -flto -fuse-ld=lld -Wl,-rpath=$libomp_installdir"
export CC=clang
export CXX=/root/dev/llvm-project/install/bin/clang++
./configure --with-openmp --with-libimagequant
make
./configure --with-openmp --with-libimagequant
make
make -j1 test V=1