https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114948
Bug ID: 114948 Summary: ICE on valid code at -O3 with "-fno-tree-ccp -fno-tree-ch" on x86_64-linux-gnu: in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:647 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 13.2 and earlier. Compiler Explorer: https://godbolt.org/z/szY6nz1W3 [522] % 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/15.0.0/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 15.0.0 20240505 (experimental) (GCC) [523] % [523] % gcctk -O3 -fno-tree-ccp -fno-tree-ch small.c during GIMPLE pass: cunroll small.c: In function ‘main’: small.c:2:5: internal compiler error: in check_loop_closed_ssa_def, at tree-ssa-loop-manip.cc:647 2 | int main() { | ^~~~ 0x89471d check_loop_closed_ssa_def ../../gcc-trunk/gcc/tree-ssa-loop-manip.cc:647 0x130e654 check_loop_closed_ssa_bb ../../gcc-trunk/gcc/tree-ssa-loop-manip.cc:661 0x131023e verify_loop_closed_ssa(bool, loop*) ../../gcc-trunk/gcc/tree-ssa-loop-manip.cc:697 0x131023e verify_loop_closed_ssa(bool, loop*) ../../gcc-trunk/gcc/tree-ssa-loop-manip.cc:681 0x12f54fe tree_unroll_loops_completely ../../gcc-trunk/gcc/tree-ssa-loop-ivcanon.cc:1569 0x12f5583 execute ../../gcc-trunk/gcc/tree-ssa-loop-ivcanon.cc:1673 0x12f5583 execute ../../gcc-trunk/gcc/tree-ssa-loop-ivcanon.cc:1663 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. [524] % [524] % cat small.c int a, b, c, d; int main() { int *e = 0; for (; d; d++) L1: ; L2: if (a) { for (c = 0; c < 2; ++c) { int *h; int **i = &h; int **const *j = &i; int **const **k = &j; if (c) { if (b) goto L2; a = *e; } } goto L1; } return 0; }