For what it's worth, yesterday I filed a GCC bug for their inconsistent constexpr behavior (thanks to André for tracking it down to array vs non-array).
Bug 1530937 Comment 38 Edit History
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For what it's worth, yesterday I filed a GCC bug for their inconsistent constexpr behavior (thanks to André for tracking it down to array vs non-array). https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89599