https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83957
Bug ID: 83957 Summary: ICE: Segmentation fault (in gimple_phi_arg) Product: gcc Version: unknown Status: UNCONFIRMED Keywords: ice-on-valid-code Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: asolokha at gmx dot com Target Milestone: --- gcc-8.0.0-alpha20180114 snapshot (r256677), 7.2, and 6.3 all ICE when compiling the following snippet w/ -O1 -ftree-parallelize-loops=2 -fno-tree-dce --param parloops-schedule=runtime (=dynamic, =guided): void k2 (int *ch, int fw) { for (*ch = 0; *ch < 16; ++*ch) { } fw += *ch & 1; if (fw < 0) while (fw < 1) { ch = &fw; ++fw; } } % gcc-8.0.0-alpha20180114 -O1 -ftree-parallelize-loops=2 -fno-tree-dce --param parloops-schedule=runtime -c clnvri9r.c during GIMPLE pass: ompexpssa clnvri9r.c: In function 'k2': clnvri9r.c:10:11: internal compiler error: Segmentation fault while (fw < 1) ^ 0xc9910f crash_signal /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/toplev.c:325 0xb7719e gimple_phi_arg /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/gimple.h:4368 0xb7719e gimple_phi_arg_def /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/gimple.h:4413 0xb7719e expand_omp_for_generic /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/omp-expand.c:3172 0xb79c3e expand_omp_for /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/omp-expand.c:5700 0xb7a0da expand_omp /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/omp-expand.c:7730 0xb7a557 expand_omp /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/omp-expand.c:7716 0xb7bd1d execute_expand_omp /var/tmp/portage/sys-devel/gcc-8.0.0_alpha20180114/work/gcc-8-20180114/gcc/omp-expand.c:7954 Earlier gcc versions don't have parloops-schedule parameter.