https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86369
--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> --- (In reply to Aaron Ballman from comment #9) > Doesn't [expr.eq] make it unspecified though? Will defer that answer to Jason. But please have a look at the comment 6 testcase. I strongly hope that constexpr const char *p = "abc"; constexpr const char *q = p; static_assert (p == q, ""); doesn't actually mean the string literal is evaluated multiple times, because if it would be, then one pretty much can't use string literals for anything reliably. I bet the wording in there is for the constexpr const char *r = "abc"; constexpr const char *s = "abc"; case, where the standard doesn't force implementations to unify same string literals within the same TU but allows it (and also allows say tail merging of them). From what I can see in the LLVM constant expression evaluation behavior, it doesn't track what comes from which evaluation of a string literal (GCC doesn't track that either) and just assumes that it could be different evaluation, while GCC assumes it is not.
