https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61942
--- Comment #2 from Vittorio Zecca <zeccav at gmail dot com> --- This is what I get on x86-64 with a sanitized version of gcc: ~/local/gcc-4.9.1-sanitized/bin/gcc -S gccerr12.c -funroll-loops -O3 ../../gcc-4.9.1/gcc/loop-iv.c:2272:24: runtime error: signed integer overflow: 9223372036854775807 - -9223372036854775808 cannot be represented in type 'long int' Please note the -funroll-loops -O3 options.