https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110137
--- Comment #21 from Jason Merrill <jason at gcc dot gnu.org> --- (In reply to Richard Biener from comment #20) > It still uses/clobbers global memory though. Hmm, I guess that's a separate issue from being able to elide the calls entirely, which is what CALL_FROM_NEW_OR_DELETE_P (and apparently __builtin_operator_new) means. If the calls aren't elided, they could still mess with global memory, and that's what -fassume-sane-operator-new is for? The testcase in comment 15 suggests that -fassume-sane-operator-new doesn't also imply elidability. So I suppose using the same flag won't work after all, they seem to be different properties.
