https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110676
--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:d3eac7d96de790df51859f63c13838f153b416de commit r14-8825-gd3eac7d96de790df51859f63c13838f153b416de Author: Jakub Jelinek <ja...@redhat.com> Date: Tue Feb 6 13:00:04 2024 +0100 asan: Don't fold some strlens with -fsanitize=address [PR110676] The UB on the following testcase isn't diagnosed by -fsanitize=address, because we see that the array has a single element and optimize the strlen to 0. I think it is fine to assume e.g. for range purposes the lower bound for the strlen as long as we don't try to optimize strlen (str) where we know that it returns [26, 42] to 26 + strlen (str + 26), but for the upper bound we really want to punt on optimizing that for -fsanitize=address to read all the bytes of the string and diagnose if we run to object end etc. 2024-02-06 Jakub Jelinek <ja...@redhat.com> PR sanitizer/110676 * gimple-fold.cc (gimple_fold_builtin_strlen): For -fsanitize=address reset maxlen to sizetype maximum. * gcc.dg/asan/pr110676.c: New test.