https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68830
Bug ID: 68830 Summary: internal compiler error: in tree_ssa_phiopt_worker, at tree-ssa-phiopt.c:322 Product: gcc Version: 6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: regehr at cs dot utah.edu Target Milestone: --- ICE on valid code $ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/home/john/gcc-install/libexec/gcc/x86_64-pc-linux-gnu/6.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../configure --prefix=/home/john/gcc-install --enable-languages=c,c++ Thread model: posix gcc version 6.0.0 20151208 (experimental) (GCC) $ cat small.c long a; unsigned short b; int c; void fn1() { long d; int e[5][7]; e[1][3] = 1; for (;;) if (d) { char f = c = 1; for (; c <= 4; c++) { a = 0; for (;; a++) { if (e[c][a + 1]) break; b &= f; e[c][a] = 0; } } } } $ gcc -O3 -c small.c small.c: In function ‘fn1’: small.c:4:6: internal compiler error: in tree_ssa_phiopt_worker, at tree-ssa-phiopt.c:322 void fn1() { ^~~ 0xc8390e tree_ssa_phiopt_worker ../../gcc/tree-ssa-phiopt.c:322 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. john@tis-HP-Z440-Workstation:~/test/reduce_crash_325170$