https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82494
David Binderman <dcb314 at hotmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |dcb314 at hotmail dot com --- Comment #2 from David Binderman <dcb314 at hotmail dot com> --- I tried a -fsanitize=undefined build of today's gcc trunk with -O3 and the runtime errors I found are: $ grep error: mk.out ../../trunk/gcc/tree-data-ref.c:3640:26: runtime error: signed integer overflow: 9223372036854775807 - -1 cannot be represented in type 'long int [3]' ../../trunk/gcc/tree-data-ref.c:3642:52: runtime error: signed integer overflow: -9223372036854775808 - 1 cannot be represented in type 'long int [3]' $