[Bug sanitizer/60557] UBSAN: ICE after ubsan_expand_null_ifn

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60557

--- Comment #6 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #5)
> This should hopefully fix it.

Looks good to me. For the testcase of comment 1, it also gives the expected
run-time diagnostic:

test.f90:19: runtime error: signed integer overflow: 809078955 * 65539 cannot
be represented in type 'integer(kind=4)'