https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111043
--- Comment #9 from Zhendong Su <zhendong.su at inf dot ethz.ch> --- Another at -O2 and -O3: [545] % 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/14.0.0/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 14.0.0 20231101 (experimental) (GCC) [546] % [546] % gcctk -O2 small.c during GIMPLE pass: ch_vect small.c: In function ‘main’: small.c:21:5: internal compiler error: in adjust_loop_info_after_peeling, at tree-ssa-loop-ivcanon.cc:1069 21 | int main() { | ^~~~ 0x8736bd adjust_loop_info_after_peeling(loop*, int, bool) ../../gcc-trunk/gcc/tree-ssa-loop-ivcanon.cc:1069 0x1287a14 copy_headers ../../gcc-trunk/gcc/tree-ssa-loop-ch.cc:1108 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. [547] % [547] % cat small.c int a, *b, c, *d, e, f; static void g() { int h; while (1) while (1) { int *i = 0; h = 0; while (c) *d = 1; if (e) break; if ((h ^ f) > f) for (; e < 1; e++) ; for (a = 0; a < 1; a++) if (*i) break; b = &h; } } int main() { if (a) g(); return 0; }