https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103121
--- Comment #28 from rguenther at suse dot de <rguenther at suse dot de> --- On Thu, 20 Jan 2022, msebor at gcc dot gnu.org wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103121 > > --- Comment #26 from Martin Sebor <msebor at gcc dot gnu.org> --- > (In reply to rguent...@suse.de from comment #23) > ... > The cache stores the offset of the pointer SSA_NAME at its definition. Since > the SSA_NAME never changes, the context doesn't matter. Or am I missing > something? Consider ptr_1 = &a + _2; if (_2 == 0) use1 (ptr_1); use2 (ptr_1); if we visit use1 and ask ptr-query for ptr_1 with context 'use1' I expect it to record offset 0 (_2 == 0) from &a at the ptr_1 definition in the cache. When we then proceed to use2 and ask ptr-query for ptr_1 with context 'use2' it will find the cached &a + 0, won't it? And that would be wrong here. But as said I only briefly looked at how things work but it does seem that the ability to specify a context to ptr_query but caching things for SSA definitions with query results which use those context can lead to wrong answers down the road.
