https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68133
Daniel Krügler <daniel.kruegler at googlemail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |daniel.kruegler@googlemail. | |com --- Comment #1 from Daniel Krügler <daniel.kruegler at googlemail dot com> --- The implementation matches the required semantics (see http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4529.html). Please note that std::char_traits::length is not constexpr because it is specified that way and this is a known library issue, see http://cplusplus.github.io/LWG/lwg-active.html#2232 The reason why the discussed string view constructor is nonetheless declared as constexpr is due to the fact that a user *could* instantiate it with a user-defined char trait class (not necessarily a specialization of std::char_traits) that *has* a constexpr length function. Based on this argumentation this issue looks invalid to me.