http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52996
Bug #: 52996 Summary: ice in verify_loop_structure, at cfgloop.c:1567 Classification: Unclassified Product: gcc Version: 4.8.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassig...@gcc.gnu.org ReportedBy: reg...@cs.utah.edu CC: cheny...@cs.utah.edu [regehr@dyson r33]$ current-gcc -O3 -c small.c small.c: In function 'fn1': small.c:29:1: error: edge from 18 to 19 should be marked irreducible } ^ small.c:29:1: error: basic block 19 should be marked irreducible } ^ small.c:29:1: error: edge from 19 to 11 should be marked irreducible } ^ small.c:29:1: internal compiler error: in verify_loop_structure, at cfgloop.c:1567 } ^ Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. [regehr@dyson r33]$ cat small.c int a, b, c, d, e, f; void fn1 () { int g, h; lbl_173: if (a) c++; lbl_158: e = 0; h = 0; for (; h > -8; h--) { g = 0; for (; g <= 0; g += 1) { d = 1; for (; d >= 0; d -= 1) a = 1; if (b) break; if (f) return; if (h) goto lbl_158; } } goto lbl_173; } [regehr@dyson r33]$ current-gcc -v Using built-in specs. COLLECT_GCC=current-gcc COLLECT_LTO_WRAPPER=/uusoc/exports/scratch/regehr/z/compiler-install/gcc-r186455-install/bin/../libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper Target: x86_64-unknown-linux-gnu Configured with: ../configure --with-libelf=/usr/local --enable-lto --prefix=/home/regehr/z/compiler-install/gcc-r186455-install --program-prefix=r186455- --enable-languages=c,c++ Thread model: posix gcc version 4.8.0 20120414 (experimental) (GCC)