Do the operator= SFINAE in the return type for optional,
commit3bc1283b7cfeacc2274369a424b0e17b88909719
authorville <ville@138bc75d-0d04-0410-961f-82ee72b054a4>
Thu, 20 Oct 2016 11:54:52 +0000 (20 11:54 +0000)
committerville <ville@138bc75d-0d04-0410-961f-82ee72b054a4>
Thu, 20 Oct 2016 11:54:52 +0000 (20 11:54 +0000)
treee918f7173f1a80275990376780df8b568e73df2c
parent389d32e559b83d1d2bfea9666639d357893d0ff1
Do the operator= SFINAE in the return type for optional,
not in the template parameters.
* include/std/optional (operator=(_Up&&)): Move SFINAE
from template parameters to the return type.
(operator=(const optional<_Up>&)): Likewise.
(operator=(optional<_Up>&&)): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@241372 138bc75d-0d04-0410-961f-82ee72b054a4
libstdc++-v3/ChangeLog
libstdc++-v3/include/std/optional