re PR c++/55357 (-Wshadow warns about lambda function parameters matching variables in outer scope)

	PR c++/55357
	* semantics.c (maybe_add_lambda_conv_op): Clear DECL_NAME of copied
	parms to avoid duplicate -Wshadow warnings.

From-SVN: r196739

gcc/cp/ChangeLog

 2013-03-16  Jason Merrill  <jason@redhat.com>
 
+	PR c++/55357
+	* semantics.c (maybe_add_lambda_conv_op): Clear DECL_NAME of copied
+	parms to avoid duplicate -Wshadow warnings.
+
 	* search.c (lookup_base): Handle NULL_TREE.
 
 	PR c++/56481

gcc/cp/semantics.c

@@ -9678,7 +9678,11 @@ maybe_add_lambda_conv_op (tree type)
   DECL_STATIC_FUNCTION_P (fn) = 1;
   DECL_ARGUMENTS (fn) = copy_list (DECL_CHAIN (DECL_ARGUMENTS (callop)));
   for (arg = DECL_ARGUMENTS (fn); arg; arg = DECL_CHAIN (arg))
-    DECL_CONTEXT (arg) = fn;
+    {
+      /* Avoid duplicate -Wshadow warnings.  */
+      DECL_NAME (arg) = NULL_TREE;
+      DECL_CONTEXT (arg) = fn;
+    }
   if (nested)
     DECL_INTERFACE_KNOWN (fn) = 1;
 

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-shadow1.C

+// PR c++/55357
+// { dg-options "-std=c++11 -Wshadow" }
+
+int main() {
+  int x = 1;			  // { dg-warning "shadowed" }
+  auto const lambda = [](int x) { // { dg-warning "shadows" }
+    return x;
+  };
+}