decl.c (create_array_type_for_decl): Only warn about invalid C++1y VLA if flag_iso or warn_vla>0.

	* decl.c (create_array_type_for_decl): Only warn about invalid
	C++1y VLA if flag_iso or warn_vla>0.
	(grokdeclarator): Likewise.
	* pt.c (tsubst): Likewise.
	* semantics.c (finish_decltype_type): Likewise.
	* typeck.c (cxx_sizeof_or_alignof_type): Likewise.
	(cp_build_addr_expr_1): Likewise.
	* init.c (build_new_1): Improve diagnostics.

From-SVN: r208411

gcc/cp/ChangeLog

+2014-03-07  Jason Merrill  <jason@redhat.com>
+
+	* decl.c (create_array_type_for_decl): Only warn about invalid
+	C++1y VLA if flag_iso or warn_vla>0.
+	(grokdeclarator): Likewise.
+	* pt.c (tsubst): Likewise.
+	* semantics.c (finish_decltype_type): Likewise.
+	* typeck.c (cxx_sizeof_or_alignof_type): Likewise.
+	(cp_build_addr_expr_1): Likewise.
+	* init.c (build_new_1): Improve diagnostics.
+
 2014-03-07  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/58609

gcc/cp/decl.c

@@ -8530,7 +8530,8 @@ create_array_type_for_decl (tree name, tree type, tree size)
       return error_mark_node;
     }
 
-  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type))
+  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type)
+      && (flag_iso || warn_vla > 0))
     pedwarn (input_location, OPT_Wvla, "array of array of runtime bound");
 
   /* Figure out the index type for the array.  */
@@ -9762,7 +9763,8 @@ grokdeclarator (const cp_declarator *declarator,
                    : G_("cannot declare pointer to qualified function type %qT"),
 		   type);
 
-	  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type))
+	  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type)
+	      && (flag_iso || warn_vla > 0))
 	    pedwarn (input_location, OPT_Wvla,
 		     declarator->kind == cdk_reference
 		     ? G_("reference to array of runtime bound")
@@ -10110,7 +10112,8 @@ grokdeclarator (const cp_declarator *declarator,
 	  type = error_mark_node;
 	}
 
-      if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type))
+      if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type)
+	  && (flag_iso || warn_vla > 0))
 	pedwarn (input_location, OPT_Wvla,
 		 "typedef naming array of runtime bound");
 

gcc/cp/init.c

@@ -2285,6 +2285,7 @@ build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
      is therefore reusable.  */
   tree data_addr;
   tree init_preeval_expr = NULL_TREE;
+  tree orig_type = type;
 
   if (nelts)
     {
@@ -2330,7 +2331,7 @@ build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
 	  if (complain & tf_error)
 	    {
 	      error_at (EXPR_LOC_OR_LOC (inner_nelts, input_location),
-			"array size in operator new must be constant");
+			"array size in new-expression must be constant");
 	      cxx_constant_value(inner_nelts);
 	    }
 	  nelts = error_mark_node;
@@ -2344,7 +2345,7 @@ build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
 
   if (variably_modified_type_p (elt_type, NULL_TREE) && (complain & tf_error))
     {
-      error ("variably modified type not allowed in operator new");
+      error ("variably modified type not allowed in new-expression");
       return error_mark_node;
     }
 
@@ -2357,8 +2358,17 @@ build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
       && !TREE_CONSTANT (maybe_constant_value (outer_nelts)))
     {
       if (complain & tf_warning_or_error)
-	pedwarn(EXPR_LOC_OR_LOC (outer_nelts, input_location), OPT_Wvla,
-		"ISO C++ does not support variable-length array types");
+	{
+	  const char *msg;
+	  if (typedef_variant_p (orig_type))
+	    msg = ("non-constant array new length must be specified "
+		   "directly, not by typedef");
+	  else
+	    msg = ("non-constant array new length must be specified "
+		   "without parentheses around the type-id");
+	  pedwarn (EXPR_LOC_OR_LOC (outer_nelts, input_location),
+		   OPT_Wvla, msg);
+	}
       else
 	return error_mark_node;
     }

gcc/cp/pt.c

@@ -11954,7 +11954,8 @@ tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
 
 	if (cxx_dialect >= cxx1y
 	    && !(TREE_CODE (t) == REFERENCE_TYPE && REFERENCE_VLA_OK (t))
-	    && array_of_runtime_bound_p (type))
+	    && array_of_runtime_bound_p (type)
+	    && (flag_iso || warn_vla > 0))
 	  {
 	    if (complain & tf_warning_or_error)
 	      pedwarn

gcc/cp/semantics.c

@@ -7031,7 +7031,8 @@ finish_decltype_type (tree expr, bool id_expression_or_member_access_p,
 	}
     }
 
-  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type))
+  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type)
+      && (flag_iso || warn_vla > 0))
     {
       if (complain & tf_warning_or_error)
 	pedwarn (input_location, OPT_Wvla,

gcc/cp/typeck.c

@@ -1552,7 +1552,8 @@ cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
       return value;
     }
 
-  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type))
+  if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (type)
+      && (flag_iso || warn_vla > 0))
     {
       if (complain & tf_warning_or_error)
 	pedwarn (input_location, OPT_Wvla,
@@ -5471,7 +5472,8 @@ cp_build_addr_expr_1 (tree arg, bool strict_lvalue, tsubst_flags_t complain)
 
   if (argtype != error_mark_node)
     {
-      if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (argtype))
+      if (cxx_dialect >= cxx1y && array_of_runtime_bound_p (argtype)
+	  && (flag_iso || warn_vla > 0))
 	{
 	  if (complain & tf_warning_or_error)
 	    pedwarn (input_location, OPT_Wvla,

gcc/testsuite/g++.dg/ext/vla1.C

@@ -9,7 +9,7 @@ class A { A (int); };
 
 A::A (int i)
 {
-  int ar[1][i];    // { dg-error "variable length array" }
+  int ar[1][i];    // { dg-error "array" }
 
   ar[0][0] = 0;
 }

gcc/testsuite/g++.dg/ext/vla5.C

@@ -6,5 +6,5 @@
 void
 test (int a)
 {
-  new (char[a]); // { dg-warning "variable-length array" }
+  new (char[a]); // { dg-warning "parentheses" }
 }

gcc/testsuite/g++.dg/ext/vla8.C

@@ -8,7 +8,7 @@ struct AvlTreeIter
 
   AvlTreeIter()
   {
-    new (void* [Num()]); // { dg-warning "variable-length array" }
+    new (void* [Num()]); // { dg-warning "parentheses" }
   }
 };
 

gcc/testsuite/g++.dg/init/new35.C

@@ -5,7 +5,7 @@ int
 main (int argc, char **argv)
 {
   typedef char A[argc];
-  new A; // { dg-warning "variable-length array types|not a constant" }
+  new A; // { dg-warning "array" }
   new A[0]; // { dg-error "must be constant|not a constant" }
   new A[5]; // { dg-error "must be constant|not a constant" }
   new (A[0]); // { dg-error "must be constant|not a constant" }

gcc/testsuite/g++.dg/init/new37.C

@@ -3,7 +3,7 @@
 void
 nonconst(int n)
 {
-  new (long[n][n]); // { dg-error "variable length|array size|not a constant" }
+  new (long[n][n]); // { dg-error "variable length|array size|not a constant|runtime bound" }
   new long[n][n]; // { dg-error "variable length|array size|not a constant" }
 }