https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118805
Bug ID: 118805
Summary: wrong code at -O1 with "-fno-tree-ccp
-fno-tree-copy-prop -fno-tree-forwprop -fno-tree-fre"
on x86_64-linux-gnu
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zhendong.su at inf dot ethz.ch
Target Milestone: ---
It appears to be a recent regression as it doesn't reproduce with 14.2 and
earlier.
Compiler Explorer: https://godbolt.org/z/P91rdM1Px
[585] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/15.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror --enable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 15.0.1 20250209 (experimental) (GCC)
[586] %
[586] % gcctk -O1 small.c; ./a.out
[587] %
[587] % gcctk -O1 -fno-tree-ccp -fno-tree-copy-prop -fno-tree-forwprop
-fno-tree-fre small.c
[588] % ./a.out
Aborted
[589] %
[589] % cat small.c
unsigned char a = 255;
int b;
int main() {
int c = 0;
if (c > a && a >= 255)
__builtin_abort();
return 0;
}
