https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55004 Bug 55004 depends on bug 67333, which changed state.
Bug 67333 Summary: [C++11][constexpr] constexpr functions incorrectly prohibit taking references to volatile types https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67333 What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED Resolution|--- |FIXED
