CWG 2094 - volatile scalars are trivially copyable.

	PR c++/85679
	* tree.c (trivially_copyable_p): Don't check CP_TYPE_VOLATILE_P for
	scalar types.

	* g++.dg/ext/is_trivially_constructible1.C: Change the expected result
	for volatile int.
	* g++.dg/ext/is_trivially_copyable.C: New test.

	* testsuite/20_util/is_trivially_copyable/value.cc: Change the expected
	result for volatile int.

From-SVN: r271435

gcc/cp/ChangeLog

 2019-05-20  Marek Polacek  <polacek@redhat.com>
 
+	CWG 2094 - volatile scalars are trivially copyable.
+	PR c++/85679
+	* tree.c (trivially_copyable_p): Don't check CP_TYPE_VOLATILE_P for
+	scalar types.
+
+2019-05-20  Marek Polacek  <polacek@redhat.com>
+
 	* pt.c (convert_template_argument): Add a diagnostic for the
 	[temp.arg]/2 ambiguity case.
 

gcc/cp/tree.c

@@ -4098,7 +4098,8 @@ trivially_copyable_p (const_tree t)
 	    && !TYPE_HAS_COMPLEX_MOVE_ASSIGN (t)
 	    && TYPE_HAS_TRIVIAL_DESTRUCTOR (t));
   else
-    return !CP_TYPE_VOLATILE_P (t) && scalarish_type_p (t);
+    /* CWG 2094 makes volatile-qualified scalars trivially copyable again.  */
+    return scalarish_type_p (t);
 }
 
 /* Returns 1 iff type T is a trivial type, as defined in [basic.types] and

gcc/testsuite/ChangeLog

 2019-05-20  Marek Polacek  <polacek@redhat.com>
 
+	CWG 2094 - volatile scalars are trivially copyable.
+	PR c++/85679
+	* g++.dg/ext/is_trivially_constructible1.C: Change the expected result
+	for volatile int.
+	* g++.dg/ext/is_trivially_copyable.C: New test.
+
+2019-05-20  Marek Polacek  <polacek@redhat.com>
+
 	* g++.dg/ext/utf8-2.C: Accept both "char" and "char8_t" in aka.
 
 	* g++.dg/cpp2a/nontype-class17.C: New test.

gcc/testsuite/g++.dg/ext/is_trivially_constructible1.C

@@ -48,7 +48,9 @@ SA(!__is_trivially_constructible(int*, const int*));
 SA(!__is_trivially_constructible(D));
 
 SA(__is_trivially_copyable(int));
-SA(!__is_trivially_copyable(volatile int));
+// Changed in CWG 2094, which made volatile-qualified scalars trivially
+// copyable.
+SA(__is_trivially_copyable(volatile int));
 
 struct E1 {const int val;};
 SA(__is_trivially_copyable(E1));

gcc/testsuite/g++.dg/ext/is_trivially_copyable.C

+// CWG 2094 - volatile scalars are trivially copyable.
+// PR c++/85679
+// { dg-do compile { target c++11 } }
+
+#define SA(X) static_assert((X),#X)
+
+struct S{};
+
+SA(__is_trivially_copyable(S volatile));
+SA(__is_trivially_copyable(S volatile[]));
+SA(__is_trivially_copyable(S const volatile));
+SA(__is_trivially_copyable(S const volatile[]));
+SA(__is_trivially_copyable(int volatile));
+SA(__is_trivially_copyable(int volatile[]));
+SA(__is_trivially_copyable(int const volatile));
+SA(__is_trivially_copyable(int const volatile[]));

libstdc++-v3/ChangeLog

+2019-05-20  Marek Polacek  <polacek@redhat.com>
+
+	CWG 2094 - volatile scalars are trivially copyable.
+	PR c++/85679
+	* testsuite/20_util/is_trivially_copyable/value.cc: Change the expected
+	result for volatile int.
+
 2019-05-20  Jonathan Wakely  <jwakely@redhat.com>
 
 	* testsuite/17_intro/names.cc: Do not check 'ptr' on Solaris.

libstdc++-v3/testsuite/20_util/is_trivially_copyable/value.cc

@@ -46,8 +46,10 @@ void test01()
 
   static_assert(test_property<is_trivially_copyable, 
 		int>(true), "");
+  // Changed in CWG 2094, which made volatile-qualified scalars trivially
+  // copyable.
   static_assert(test_property<is_trivially_copyable,
-		volatile int>(false), "");
+		volatile int>(true), "");
   static_assert(test_property<is_trivially_copyable, 
 		TType>(true), "");
   static_assert(test_property<is_trivially_copyable,