[Bug libstdc++/77537] [6 Regression] pair constructors do not properly SFINAE

[ville.voutilainen at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77537

Ville Voutilainen <ville.voutilainen at gmail dot com> changed:

           What    |Removed                     |Added
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             Status|REOPENED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #10 from Ville Voutilainen <ville.voutilainen at gmail dot com> ---
Fixed on gcc-6 branch, thus done.