re PR c++/55520 ([C++11] ICE when capturing a variable-length stack array in lambda; in expand_expr_real_1, at expr.c:9122)

PR c++/55520
	* semantics.c (add_capture): Diagnose capture of variable-size
	type that is not a C++1y array of runtime bound.

From-SVN: r199780

gcc/cp/ChangeLog

@@ -1,5 +1,9 @@
 2013-06-06  Jason Merrill  <jason@redhat.com>
 
+	PR c++/55520
+	* semantics.c (add_capture): Diagnose capture of variable-size
+	type that is not a C++1y array of runtime bound.
+
 	* decl.c (grokdeclarator): Keep a decl with error type.
 	(grokfield, grokbitfield): Likewise.
 	* pt.c (instantiate_class_template_1): Likewise.

gcc/cp/semantics.c

@@ -9487,6 +9487,15 @@ add_capture (tree lambda, tree id, tree initializer, bool by_reference_p,
 					  nelts_field, array_type_nelts (type));
       type = ctype;
     }
+  else if (variably_modified_type_p (type, NULL_TREE))
+    {
+      error ("capture of variable-size type %qT that is not a C++1y array "
+	     "of runtime bound", type);
+      if (TREE_CODE (type) == ARRAY_TYPE
+	  && variably_modified_type_p (TREE_TYPE (type), NULL_TREE))
+	inform (input_location, "because the array element type %qT has "
+		"variable size", TREE_TYPE (type));
+    }
   else if (by_reference_p)
     {
       type = build_reference_type (type);

gcc/testsuite/g++.dg/cpp1y/vla7.C

@@ -0,0 +1,12 @@
+// PR c++/55520
+// { dg-options "-Wno-vla" }
+// { dg-require-effective-target c++11 }
+
+int main(int argc, char** argv)
+{
+  int x[1][argc];
+
+  [&x](int i) {			// { dg-error "variable.size" }
+    x[0][i] = 0;	     	// { dg-prune-output "assignment" }
+  }(5);
+}