Modernize conversion to bool to the explicit bool conversion operator (library wide).  This fixes http://llvm.org/bugs/show_bug.cgi?id=12058.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@151088 91177308-0d34-0410-b5e6-96231b3b80d8

include/__config

diff --git a/include/__config b/include/__config
index 5e0db7c..6d551c9 100644
--- a/include/__config
+++ b/include/__config
@@ -376,6 +376,12 @@
 #define __has_feature(__x) 0
 #endif
 
+#if __has_feature(cxx_explicit_conversions)
+#   define _LIBCPP_EXPLICIT explicit
+#else
+#   define _LIBCPP_EXPLICIT
+#endif
+
 #ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
 #define _LIBCPP_DECLARE_STRONG_ENUM(x) struct _LIBCPP_VISIBLE x { enum _
 #define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x) \

include/__mutex_base

diff --git a/include/__mutex_base b/include/__mutex_base
index 5568765..5410272 100644
--- a/include/__mutex_base
+++ b/include/__mutex_base
@@ -207,7 +207,7 @@
     _LIBCPP_INLINE_VISIBILITY
     bool owns_lock() const {return __owns_;}
     _LIBCPP_INLINE_VISIBILITY
-//    explicit
+    _LIBCPP_EXPLICIT
         operator bool () const {return __owns_;}
     _LIBCPP_INLINE_VISIBILITY
     mutex_type* mutex() const {return __m_;}

include/exception

diff --git a/include/exception b/include/exception
index dcef3e5..f7c3b70 100644
--- a/include/exception
+++ b/include/exception
@@ -132,7 +132,7 @@
     ~exception_ptr() _NOEXCEPT;
 
     _LIBCPP_INLINE_VISIBILITY
-    // explicit
+    _LIBCPP_EXPLICIT
         operator bool() const _NOEXCEPT {return __ptr_ != nullptr;}
 
     friend _LIBCPP_INLINE_VISIBILITY

include/functional

diff --git a/include/functional b/include/functional
index 8f912fb..f941df2 100644
--- a/include/functional
+++ b/include/functional
@@ -1163,7 +1163,7 @@
 
     // function capacity:
     _LIBCPP_INLINE_VISIBILITY
-    /*explicit*/ operator bool() const _NOEXCEPT {return __f_;}
+        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return __f_;}
 
     // deleted overloads close possible hole in the type system
     template<class _R2, class... _ArgTypes2>

include/ios

diff --git a/include/ios b/include/ios
index 3aa066b..51d5087 100644
--- a/include/ios
+++ b/include/ios
@@ -572,7 +572,8 @@
     typedef typename traits_type::pos_type pos_type;
     typedef typename traits_type::off_type off_type;
 
-    _LIBCPP_ALWAYS_INLINE // explicit
+    _LIBCPP_ALWAYS_INLINE
+        _LIBCPP_EXPLICIT
         operator bool() const {return !fail();}
     _LIBCPP_ALWAYS_INLINE bool operator!() const    {return  fail();}
     _LIBCPP_ALWAYS_INLINE iostate rdstate() const   {return ios_base::rdstate();}

include/istream

diff --git a/include/istream b/include/istream
index c220532..7312425 100644
--- a/include/istream
+++ b/include/istream
@@ -256,7 +256,7 @@
 //    ~sentry() = default;
 
     _LIBCPP_INLINE_VISIBILITY
-    // explicit
+        _LIBCPP_EXPLICIT
         operator bool() const {return __ok_;}
 };
 

include/memory

diff --git a/include/memory b/include/memory
index e3dd467..aa24f96 100644
--- a/include/memory
+++ b/include/memory
@@ -2688,9 +2688,9 @@
         {return __ptr_.second();}
     _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
         {return __ptr_.second();}
-    _LIBCPP_INLINE_VISIBILITY operator int __nat::*() const
-             _NOEXCEPT
-        {return __ptr_.first() ? &__nat::__for_bool_ : 0;}
+    _LIBCPP_INLINE_VISIBILITY
+        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
+        {return __ptr_.first() != nullptr;}
 
     _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
     {
@@ -2881,8 +2881,9 @@
         {return __ptr_.second();}
     _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
         {return __ptr_.second();}
-    _LIBCPP_INLINE_VISIBILITY operator int __nat::*() const _NOEXCEPT
-        {return __ptr_.first() ? &__nat::__for_bool_ : 0;}
+    _LIBCPP_INLINE_VISIBILITY
+        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
+        {return __ptr_.first() != nullptr;}
 
     _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
     {
@@ -3937,7 +3938,7 @@
     _LIBCPP_INLINE_VISIBILITY
     bool unique() const _NOEXCEPT {return use_count() == 1;}
     _LIBCPP_INLINE_VISIBILITY
-    /*explicit*/ operator bool() const _NOEXCEPT {return get() != 0;}
+    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return get() != 0;}
     template <class _Up>
         _LIBCPP_INLINE_VISIBILITY
         bool owner_before(shared_ptr<_Up> const& __p) const

include/ostream

diff --git a/include/ostream b/include/ostream
index c4e6b38..e6dd4b5 100644
--- a/include/ostream
+++ b/include/ostream
@@ -220,7 +220,7 @@
     ~sentry();
 
     _LIBCPP_ALWAYS_INLINE
-    // explicit
+        _LIBCPP_EXPLICIT
         operator bool() const {return __ok_;}
 };
 

include/system_error

diff --git a/include/system_error b/include/system_error
index 971be33..805c646 100644
--- a/include/system_error
+++ b/include/system_error
@@ -451,7 +451,7 @@
     string message() const;
 
     _LIBCPP_ALWAYS_INLINE
-    //explicit
+        _LIBCPP_EXPLICIT
         operator bool() const _NOEXCEPT {return __val_ != 0;}
 };
 
@@ -528,7 +528,7 @@
     string message() const;
 
     _LIBCPP_ALWAYS_INLINE
-    //explicit
+        _LIBCPP_EXPLICIT
         operator bool() const _NOEXCEPT {return __val_ != 0;}
 };