From: Jonathan Wakely <jwakely@redhat.com>
Date: Thu, 2 May 2019 21:23:38 +0000 (+0100)
Subject: PR libstdc++/90314 fix non-equivalent declarations of std::swap
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=315f8b5f18dcfcd81401c9629deaf77443fa7c1e;p=gcc.git

PR libstdc++/90314 fix non-equivalent declarations of std::swap

In order to use the _GLIBCXX_NOEXCEPT_IF macro for an expression
containing commas I enclosed it in parentheses, so the preprocessor
wouldn't treat it as two arguments to the function-like macro. Clang
gives an error because now the noexcept-specifier noexcept((C)) is not
equivalent to the noexcept(C) one on the declaration of swap in
<type_traits>.

Instead of requiring extra parentheses around the expression, redefine
_GLIBCXX_NOEXCEPT_IF as a variadic macro (even though supporting that in
C++98 is a GNU extension).

	PR libstdc++/90314
	* include/bits/c++config (_GLIBCXX_NOEXCEPT_IF): Use variadic macro.
	* include/bits/move.h (swap): Remove extra parentheses.

From-SVN: r270827
---

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index cd1508ee789..6c93604d318 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,9 @@
 2019-05-02  Jonathan Wakely  <jwakely@redhat.com>
 
+	PR libstdc++/90314
+	* include/bits/c++config (_GLIBCXX_NOEXCEPT_IF): Use variadic macro.
+	* include/bits/move.h (swap): Remove extra parentheses.
+
 	* include/experimental/bits/lfts_config.h: Improve doc markup.
 	* include/experimental/optional: Improve docs.
 	(_Has_addressof_mem, _Has_addressof_free, _Has_addressof)
diff --git a/libstdc++-v3/include/bits/c++config b/libstdc++-v3/include/bits/c++config
index 5016f4853de..ca1557af564 100644
--- a/libstdc++-v3/include/bits/c++config
+++ b/libstdc++-v3/include/bits/c++config
@@ -157,12 +157,12 @@
 #ifndef _GLIBCXX_NOEXCEPT
 # if __cplusplus >= 201103L
 #  define _GLIBCXX_NOEXCEPT noexcept
-#  define _GLIBCXX_NOEXCEPT_IF(_COND) noexcept(_COND)
+#  define _GLIBCXX_NOEXCEPT_IF(...) noexcept(__VA_ARGS__)
 #  define _GLIBCXX_USE_NOEXCEPT noexcept
 #  define _GLIBCXX_THROW(_EXC)
 # else
 #  define _GLIBCXX_NOEXCEPT
-#  define _GLIBCXX_NOEXCEPT_IF(_COND)
+#  define _GLIBCXX_NOEXCEPT_IF(...)
 #  define _GLIBCXX_USE_NOEXCEPT throw()
 #  define _GLIBCXX_THROW(_EXC) throw(_EXC)
 # endif
diff --git a/libstdc++-v3/include/bits/move.h b/libstdc++-v3/include/bits/move.h
index 996078cfbce..7271e273e8e 100644
--- a/libstdc++-v3/include/bits/move.h
+++ b/libstdc++-v3/include/bits/move.h
@@ -183,8 +183,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     void
 #endif
     swap(_Tp& __a, _Tp& __b)
-    _GLIBCXX_NOEXCEPT_IF((__and_<is_nothrow_move_constructible<_Tp>,
-				 is_nothrow_move_assignable<_Tp>>::value))
+    _GLIBCXX_NOEXCEPT_IF(__and_<is_nothrow_move_constructible<_Tp>,
+				is_nothrow_move_assignable<_Tp>>::value)
     {
       // concept requirements
       __glibcxx_function_requires(_SGIAssignableConcept<_Tp>)