https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107107
--- Comment #12 from CVS Commits ---
The releases/gcc-12 branch has been updated by Richard Biener
:
https://gcc.gnu.org/g:ff0a274e5c3026b105c7f51126fa51f8178fa42c
commit r12-8838-gff0a274e5c3026b105c7f51126fa51f8178fa42c
Author: Richard Biener
Date: Thu Oct 6 11:20:16 2022 +0200
tree-optimization/107107 - tail-merging VN wrong-code
The following fixes an unintended(?) side-effect of the special
MODIFY_EXPR expression entries we add for tail-merging during VN.
We shouldn't value-number the virtual operand differently here.
PR tree-optimization/107107
* tree-ssa-sccvn.cc (visit_reference_op_store): Do not
affect value-numbering when doing the tail merging
MODIFY_EXPR lookup.
* gcc.dg/pr107107.c: New testcase.
(cherry picked from commit 85333b9265720fc4e49397301cb16324d2b89aa7)