[Bug tree-optimization/61943] tree-ssa-loop-ivopts.c:4148 signed integer overflow

[zeccav at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61943

--- Comment #2 from Vittorio Zecca <zeccav at gmail dot com> ---
gcc was compiled with -fsanitize=undefined option.
Call it gcc-sanitized.
Then I did
gcc-sanitized -S gccerr13.c -O
where gccerr13.c is the sample C code I sent bugzilla
The option -O is necessary to reproduce the bug.
Error message from the sanitizer
../../gcc-4.9.1/gcc/tree-ssa-loop-ivopts.c:4148:24: runtime error:
signed integer overflow: 4 * 4611686018427387903 cannot be represented
in type 'long int'