https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105094
--- Comment #3 from CVS 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:387e818cda0ffde86f624228c3da1ab28f453685 commit r12-7916-g387e818cda0ffde86f624228c3da1ab28f453685 Author: Jakub Jelinek <ja...@redhat.com> Date: Wed Mar 30 10:21:16 2022 +0200 store-merging: Avoid ICEs on roughly ~0ULL/8 sized stores [PR105094] On the following testcase on 64-bit targets, store-merging sees a MEM_REF store from {} ctor with "negative" bitsize where bitoff + bitsize wraps around to very small end offset. This later confuses the code so that it allocates just a few bytes of memory but fills in huge amounts of it. Later on there is a param_store_merging_max_size size check but due to the wrap-around we pass that. The following patch punts on such large bitsizes. 2022-03-30 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/105094 * gimple-ssa-store-merging.cc (mem_valid_for_store_merging): Punt if bitsize <= 0 rather than just == 0. * gcc.dg/pr105094.c: New test.
