re PR c++/54538 (Getting assembler messages when compiling)

	PR c++/54538
	PR c++/53783
	* pt.c (tsubst_copy_and_build) [LAMBDA_EXPR]: Go back to using RECUR
	for LAMBDA_EXPR_EXTRA_SCOPE except for function scope.

From-SVN: r191164

gcc/cp/ChangeLog

 2012-09-10  Jason Merrill  <jason@redhat.com>
 
+	PR c++/54538
+	PR c++/53783
+	* pt.c (tsubst_copy_and_build) [LAMBDA_EXPR]: Go back to using RECUR
+	for LAMBDA_EXPR_EXTRA_SCOPE except for function scope.
+
 	PR c++/54506
 	* decl.c (move_signature_fn_p): Split out from move_fn_p.
 	* method.c (process_subob_fn): Use it.

gcc/cp/pt.c

@@ -14199,8 +14199,18 @@ tsubst_copy_and_build (tree t,
 	LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
 	LAMBDA_EXPR_DISCRIMINATOR (r)
 	  = (LAMBDA_EXPR_DISCRIMINATOR (t));
-	LAMBDA_EXPR_EXTRA_SCOPE (r)
-	  = tsubst (LAMBDA_EXPR_EXTRA_SCOPE (t), args, complain, in_decl);
+	/* For a function scope, we want to use tsubst so that we don't
+	   complain about referring to an auto function before its return
+	   type has been deduced.  Otherwise, we want to use tsubst_copy so
+	   that we look up the existing field/parameter/variable rather
+	   than build a new one.  */
+	tree scope = LAMBDA_EXPR_EXTRA_SCOPE (t);
+	if (scope && TREE_CODE (scope) == FUNCTION_DECL)
+	  scope = tsubst (LAMBDA_EXPR_EXTRA_SCOPE (t), args,
+			  complain, in_decl);
+	else
+	  scope = RECUR (scope);
+	LAMBDA_EXPR_EXTRA_SCOPE (r) = scope;
 	LAMBDA_EXPR_RETURN_TYPE (r)
 	  = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
 

gcc/testsuite/ChangeLog

+2012-09-10  Jason Merrill  <jason@redhat.com>
+
+	PR c++/54538
+	* g++.dg/cpp0x/lambda/lambda-mangle4.C: New.
+
 2012-09-10  Oleg Endo  <olegendo@gcc.gnu.org>
 
 	PR target/54089

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-mangle4.C

+// PR c++/54538
+// { dg-do compile { target c++11 } }
+
+template <class T>
+struct A
+{
+  // { dg-final { scan-assembler "_ZNK1AIcE1pMUlvE_cvPFvvEEv" } }
+  // { dg-final { scan-assembler "_ZNK1AIiE1pMUlvE_cvPFvvEEv" } }
+  void (*p)() = []{};
+};
+
+A<int> a1;
+A<char> a2;