https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121035
Bug ID: 121035
Summary: ICE on valid code at -O{2,3} with "-fno-tree-dce
-fno-tree-dse -fno-expensive-optimizations
-fno-ssa-phiopt" on x86_64-linux-gnu: Segmentation
fault
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: ---
Compiler Explorer: https://godbolt.org/z/9dcozz6ov
It appears to be a regression from 14.3 and affects 15.1 and trunk.
[606] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/home/suz/suz-local/software/local/gcc-trunk/bin/../libexec/gcc/x86_64-pc-linux-gnu/16.0.0/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 16.0.0 20250711 (experimental) (GCC)
[607] %
[607] % gcctk -O3 -fno-tree-dce -fno-tree-dse -fno-expensive-optimizations
-fno-ssa-phiopt small.c
during GIMPLE pass: pre
small.c: In function ‘main’:
small.c:4:5: internal compiler error: Segmentation fault
4 | int main() {
| ^~~~
0x255ccb6 internal_error(char const*, ...)
../../gcc-trunk/gcc/diagnostic-global-context.cc:517
0x119d693 crash_signal
../../gcc-trunk/gcc/toplev.cc:321
0x7f68bd42151f ???
./signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0
0x139c744 bmp_iter_set_init(bitmap_iterator*, bitmap_head const*, unsigned int,
unsigned int*)
../../gcc-trunk/gcc/bitmap.h:542
0x139c744 find_or_generate_expression
../../gcc-trunk/gcc/tree-ssa-pre.cc:2776
0x139bd5a find_or_generate_expression
../../gcc-trunk/gcc/tree-ssa-pre.cc:2748
0x139bd5a create_expression_by_pieces
../../gcc-trunk/gcc/tree-ssa-pre.cc:2924
0x13a0cf3 insert_into_preds_of_block
../../gcc-trunk/gcc/tree-ssa-pre.cc:3132
0x13a3710 do_pre_regular_insertion
../../gcc-trunk/gcc/tree-ssa-pre.cc:3398
0x13a3710 insert
../../gcc-trunk/gcc/tree-ssa-pre.cc:3833
0x13a3710 execute
../../gcc-trunk/gcc/tree-ssa-pre.cc:4497
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
[608] %
[608] % cat small.c
int printf(const char *, ...);
int a, b, d;
unsigned c;
int main() {
int f = 0;
while (a) {
unsigned g = c;
if (f)
printf("0");
~(c << 1);
b = ~-(a * d && 1) | g * -2 && a;
f = c;
}
return 0;
}
