https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65509
--- Comment #14 from Mitsuru Kariya <kariya_mitsuru at hotmail dot com> --- The rev.221737 seems to be able to compile the sample code above, but cannot compile another sample code like below. ================= sample code ================= constexpr char s1[] = "s1"; constexpr char s2[] = "s2"; constexpr auto eq = (s1 + 0) == (s2 + 1); int main() {} ================= sample code ================= ================ error message ================ compare2.cpp:4:30: error: '(((const char*)(& s1)) == (((const char*)(& s2)) + 1u))' is not a constant expression constexpr auto eq = (s1 + 0) == (s2 + 1); ================ error message ================ Although the first sample causes compilation error only in 5.0.0, the second sample causes compilation error in 4.9.2 too. cf. http://melpon.org/wandbox/permlink/KhcREuNqGofbZvqw