Apply constexpr to <bitset>.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@159899 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/__bit_reference b/include/__bit_reference
index 21ce11f..b91532d 100644
--- a/include/__bit_reference
+++ b/include/__bit_reference
@@ -131,13 +131,14 @@
__bit_const_reference(const __bit_reference<_Cp>& __x) _NOEXCEPT
: __seg_(__x.__seg_), __mask_(__x.__mask_) {}
- _LIBCPP_INLINE_VISIBILITY operator bool() const _NOEXCEPT
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR operator bool() const _NOEXCEPT
{return static_cast<bool>(*__seg_ & __mask_);}
_LIBCPP_INLINE_VISIBILITY __bit_iterator<_Cp, true> operator&() const _NOEXCEPT
{return __bit_iterator<_Cp, true>(__seg_, static_cast<unsigned>(__ctz(__mask_)));}
private:
_LIBCPP_INLINE_VISIBILITY
+ _LIBCPP_CONSTEXPR
__bit_const_reference(__storage_pointer __s, __storage_type __m) _NOEXCEPT
: __seg_(__s), __mask_(__m) {}