https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120358
--- Comment #35 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <rgue...@gcc.gnu.org>: https://gcc.gnu.org/g:aa5ae523e84a97bf3a582ea0fa73d959afa9b9c7 commit r16-2085-gaa5ae523e84a97bf3a582ea0fa73d959afa9b9c7 Author: Richard Biener <rguent...@suse.de> Date: Mon Jul 7 15:13:38 2025 +0200 tree-optimization/120358 - bogus PTA with structure access When we compute the constraint for something like MEM[(const struct QStringView &)&tok2 + 32] we go and compute what (const struct QStringView &)&tok2 + 32 points to and then add subvariables to its dereference that possibly fall in the range of the access according to the original refs size. In doing that we disregarded that the subvariable the starting address points to might not be aligned to it and thus the access might start at any point within that variable. The following conservatively adjusts the pruning of adjacent sub-variables to honor this. PR tree-optimization/120358 * tree-ssa-structalias.cc (get_constraint_for_1): Adjust pruning of sub-variables according to the imprecise known start offset.
