https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94295
--- Comment #4 from Richard Smith <richard-gccbugzilla at metafoo dot co.uk> --- (In reply to Andrew Pinski from comment #3) > PR 23383 is where part of the discussion was done. > > In fact GCC implements the optimization without the builtin: > https://gcc.gnu.org/legacy-ml/gcc-patches/2019-07/msg00136.html Yep, looks like GCC miscompiles direct calls to operator new / operator delete since that patch landed: https://godbolt.org/z/dK99Rz