https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105091
--- Comment #11 from Jiu Fu Guo <guojiufu at gcc dot gnu.org> --- Find one difference between trunk and r12-656: On trunk: tree expr = MEM_EXPR (mem); where mem is (mem/f/c:DI (plus:DI (reg/f:DI 110 sfp) (const_int 32 [0x20])) [3 GOTMP.2[0].x.__values+0 S8 A128]) and then expr is GOTMP.2[0].x.__values base = get_base_address (expr); base is "GOTMP.2" "may_be_aliased (base)" returns false. On r12-656: "may_be_aliased (base)" returns true. may_be_aliased checks TREE_ADDRESSABLE which also returns differences between trunk and r12-656.