Diagnose string constant conversion to char* in c++11 and above as forbidden, not deprecated.

	Diagnose string constant conversion to char* in c++11 and above
	as forbidden, not deprecated.
	* typeck.c (string_conv_p): Do a pedwarn in c++11 and above,
	change the diagnostic for the Wwrite-strings case for c++11 and above.

From-SVN: r218087

gcc/cp/ChangeLog

+2014-11-26  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	Diagnose string constant conversion to char* in c++11 and above
+	as forbidden, not deprecated.
+	* typeck.c (string_conv_p): Do a pedwarn in c++11 and above,
+	change the diagnostic for the Wwrite-strings case for c++11 and above.
+
 2014-11-24  Jason Merrill  <jason@redhat.com>
 
 	* pt.c (lookup_template_variable): Always unknown_type_node.

gcc/cp/typeck.c

@@ -2139,12 +2139,18 @@ string_conv_p (const_tree totype, const_tree exp, int warn)
 	  || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
 	return 0;
     }
-
-  /* This warning is not very useful, as it complains about printf.  */
   if (warn)
-    warning (OPT_Wwrite_strings,
-	     "deprecated conversion from string constant to %qT",
-	     totype);
+    {
+      if (cxx_dialect >= cxx11)
+	pedwarn (input_location,
+		 pedantic ? OPT_Wpedantic : OPT_Wwrite_strings,
+		 "ISO C++ forbids converting a string constant to %qT",
+		 totype);
+      else
+	warning (OPT_Wwrite_strings,
+		 "deprecated conversion from string constant to %qT",
+		 totype);
+    }
 
   return 1;
 }

gcc/testsuite/g++.dg/warn/write-strings-default.C

@@ -3,5 +3,5 @@
 
 int main()
 {
-   char* p = "Asgaard";         // { dg-warning "deprecated" }
+   char* p = "Asgaard";         // { dg-warning "deprecated|forbids converting a string constant" }
 }

gcc/testsuite/g++.dg/warn/write-strings.C

@@ -3,5 +3,5 @@
 
 int main()
 {
-   char* p = "Asgaard";         // { dg-warning "deprecated" }
+   char* p = "Asgaard";         // { dg-warning "deprecated|forbids converting a string constant" }
 }

gcc/testsuite/g++.old-deja/g++.bob/inherit1.C

@@ -12,7 +12,7 @@ public:
 class B : public A {
 public:
     char* m1 () { C::m1(); return ""; } // { dg-error "cannot call" } 
-    // { dg-warning "deprecated" "depr" { target *-*-* } 14 }
+    // { dg-warning "deprecated|forbids converting a string constant" "depr" { target *-*-* } 14 }
 };
 
 int main () {

gcc/testsuite/g++.old-deja/g++.brendan/template17.C

@@ -10,6 +10,6 @@ public:
 
 const Regex NDAMName<'L'>::pattern("^[Ll](.*)$",   1);// { dg-error "type/value mismatch" "mismatch" }
 // { dg-message "expected a type" "expected" { target *-*-* } 11 }
-// { dg-warning "deprecated" "depr" { target *-*-* } 11 }
+// { dg-warning "deprecated|forbids converting a string constant" "depr" { target *-*-* } 11 }
 unsigned NDAMName<'L'>::sequence_number = 0;// { dg-error "type/value mismatch" "mismatch" }
 // { dg-message "expected a type" "exp" { target *-*-* } 14 }

gcc/testsuite/g++.old-deja/g++.law/temps1.C

@@ -16,5 +16,5 @@ struct cookie
   cookie ( foo * x) { v=x; }
 };
 
-cookie cat(&foo("apabepa"));// { dg-warning "deprecated conversion" "dep" }
+cookie cat(&foo("apabepa"));// { dg-warning "deprecated conversion|forbids converting a string constant" "dep" }
 // { dg-warning "taking address of temporary" "add" { target *-*-* } 19 }

gcc/testsuite/g++.old-deja/g++.martin/typedef2.C

@@ -3,5 +3,5 @@
 // Check implicit conversion from string constants into typedefs
 
 typedef char CHAR;
-void f2(CHAR *s="");		// { dg-warning "deprecated" }
+void f2(CHAR *s="");		// { dg-warning "deprecated|forbids converting a string constant" }