http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57122
Bug #: 57122 Summary: ICE in verify_loop_structure, at cfgloop.c:1647 (loop n’s latch does not have an edge to its header !) Classification: Unclassified Product: gcc Version: 4.9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization AssignedTo: unassig...@gcc.gnu.org ReportedBy: antoine.balest...@gmail.com Using GCC 4.9.0 as of 20130430 : $ cat latch.c unsigned a; int b, c; void f(void) { if(a) { for(a = 0; a < 2; a++) a /= 7; for(;; a++) { if(a) lbl1: b++; if(c) goto lbl1; lbl2: ; } } goto lbl2; } $ xgcc -O2 -w latch.c latch.c: In function ‘f’: latch.c:4:6: error: loop 2’s latch does not have an edge to its header void f(void) ^ latch.c:4:6: internal compiler error: in verify_loop_structure, at cfgloop.c:1647 0x61aba5 verify_loop_structure() ../../srcdir/gcc/cfgloop.c:1647 0x7fe2ad loop_optimizer_init(unsigned int) ../../srcdir/gcc/loop-init.c:110 0xa3cf4d do_pre ../../srcdir/gcc/tree-ssa-pre.c:4708 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions.