https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117912
--- Comment #16 from Siddhesh Poyarekar <siddhesh at gcc dot gnu.org> --- (In reply to Andrew Pinski from comment #15) > (In reply to Jakub Jelinek from comment #14) > > struct S { int a; int b[24]; int c[24]; int d; }; > > void bar (int *); > > > > __SIZE_TYPE__ > > foo (struct S *p) > > { > > bar (&p->b[24]); > > bar (&p->c[0]); > > return __builtin_object_size (&p->c[0], 1); > > } Couldn't VN/CSE, when eliminating an expression involving pointers to component_refs, pick the one that points to the beginning of a component rather than the end? That should solve both these problems.