https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78455
Bug ID: 78455 Summary: [7 Regression] ICE in operator[], at vec.h:732 Product: gcc Version: 7.0 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 CC: aldyh at gcc dot gnu.org Target Milestone: --- gcc-7.0.0-alpha20161120 snapshot fails to compile the following reduced snippet w/ -O2 (-Os, -Og) -Wuninitialized: int ij; void ql (void) { int m5 = 0; for (;;) { if (0) for (;;) { int *go; int *t4 = go; l1: *t4 = (*t4 != 0) ? 0 : 2; } if (ij != 0) goto l1; } } % x86_64-unknown-linux-gnu-gcc-7.0.0-alpha20161120 -O2 -Wuninitialized -c dwgke5h1.c dwgke5h1.c: In function 'ql': dwgke5h1.c:4:1: internal compiler error: in operator[], at vec.h:732 ql (void) ^~ r242639 must be a culprit, given that the top of backtrace is this: Breakpoint 1, 0x00000000013a3db0 in internal_error(char const*, ...) () (gdb) where #0 0x00000000013a3db0 in internal_error(char const*, ...) () #1 0x00000000013a22c4 in fancy_abort(char const*, int, char const*) () #2 0x0000000000d8e861 in uninit_ops_invalidate_phi_use(gphi*, unsigned int, vec<vec<pred_info, va_heap, vl_ptr>, va_heap, vl_ptr>) () <snip>