diff --git a/include/stdexcept b/include/stdexcept
index 2ef15a6..d31dc8b 100644
--- a/include/stdexcept
+++ b/include/stdexcept
@@ -33,9 +33,9 @@
 {
 public:
     explicit xxx_error(const string& what_arg);
-    explicit xxx_error(const char*   what_arg);  // extension
+    explicit xxx_error(const char*   what_arg);
 
-    virtual const char* what() const // returns what_arg
+    virtual const char* what() const noexcept // returns what_arg
 };
 
 }  // std
@@ -60,12 +60,12 @@
     explicit logic_error(const string&);
     explicit logic_error(const char*);
 
-    logic_error(const logic_error&) throw();
-    logic_error& operator=(const logic_error&) throw();
+    logic_error(const logic_error&) _NOEXCEPT;
+    logic_error& operator=(const logic_error&) _NOEXCEPT;
 
-    virtual ~logic_error() throw();
+    virtual ~logic_error() _NOEXCEPT;
 
-    virtual const char* what() const throw();
+    virtual const char* what() const _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI runtime_error
@@ -77,12 +77,12 @@
     explicit runtime_error(const string&);
     explicit runtime_error(const char*);
 
-    runtime_error(const runtime_error&) throw();
-    runtime_error& operator=(const runtime_error&) throw();
+    runtime_error(const runtime_error&) _NOEXCEPT;
+    runtime_error& operator=(const runtime_error&) _NOEXCEPT;
 
-    virtual ~runtime_error() throw();
+    virtual ~runtime_error() _NOEXCEPT;
 
-    virtual const char* what() const throw();
+    virtual const char* what() const _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI domain_error
@@ -92,7 +92,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit domain_error(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit domain_error(const char* __s)   : logic_error(__s) {}
 
-    virtual ~domain_error() throw();
+    virtual ~domain_error() _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI invalid_argument
@@ -102,7 +102,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit invalid_argument(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit invalid_argument(const char* __s)   : logic_error(__s) {}
 
-    virtual ~invalid_argument() throw();
+    virtual ~invalid_argument() _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI length_error
@@ -112,7 +112,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit length_error(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit length_error(const char* __s)   : logic_error(__s) {}
 
-    virtual ~length_error() throw();
+    virtual ~length_error() _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI out_of_range
@@ -122,7 +122,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit out_of_range(const string& __s) : logic_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit out_of_range(const char* __s)   : logic_error(__s) {}
 
-    virtual ~out_of_range() throw();
+    virtual ~out_of_range() _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI range_error
@@ -132,7 +132,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit range_error(const string& __s) : runtime_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit range_error(const char* __s)   : runtime_error(__s) {}
 
-    virtual ~range_error() throw();
+    virtual ~range_error() _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI overflow_error
@@ -142,7 +142,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit overflow_error(const string& __s) : runtime_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit overflow_error(const char* __s)   : runtime_error(__s) {}
 
-    virtual ~overflow_error() throw();
+    virtual ~overflow_error() _NOEXCEPT;
 };
 
 class _LIBCPP_EXCEPTION_ABI underflow_error
@@ -152,7 +152,7 @@
     _LIBCPP_INLINE_VISIBILITY explicit underflow_error(const string& __s) : runtime_error(__s) {}
     _LIBCPP_INLINE_VISIBILITY explicit underflow_error(const char* __s)   : runtime_error(__s) {}
 
-    virtual ~underflow_error() throw();
+    virtual ~underflow_error() _NOEXCEPT;
 };
 
 }  // std