re PR c++/54764 (In class initialization of non-static lambda member can't be used in class with default template paramer)

PR c++/54764
	PR c++/55972
	* name-lookup.h (tag_scope): Add ts_lambda.
	* semantics.c (begin_lambda_type): Use it.
	* decl.c (xref_tag_1): Set CLASSTYPE_LAMBDA_EXPR.
	* pt.c (check_default_tmpl_args): Ignore lambdas.
	(push_template_decl_real): Handle lambdas.
	* tree.c (no_linkage_check): Adjust lambda check.

From-SVN: r196742

gcc/cp/ChangeLog

@@ -1,5 +1,14 @@
 2013-03-16  Jason Merrill  <jason@redhat.com>
 
+	PR c++/54764
+	PR c++/55972
+	* name-lookup.h (tag_scope): Add ts_lambda.
+	* semantics.c (begin_lambda_type): Use it.
+	* decl.c (xref_tag_1): Set CLASSTYPE_LAMBDA_EXPR.
+	* pt.c (check_default_tmpl_args): Ignore lambdas.
+	(push_template_decl_real): Handle lambdas.
+	* tree.c (no_linkage_check): Adjust lambda check.
+
 	PR c++/56039
 	* tree.c (strip_typedefs_expr): Complain about lambda, don't abort.
 

gcc/cp/decl.c

@@ -11887,11 +11887,12 @@ lookup_and_check_tag (enum tag_types tag_code, tree name,
 
 static tree
 xref_tag_1 (enum tag_types tag_code, tree name,
-            tag_scope scope, bool template_header_p)
+            tag_scope orig_scope, bool template_header_p)
 {
   enum tree_code code;
   tree t;
   tree context = NULL_TREE;
+  tag_scope scope;
 
   gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
 
@@ -11911,6 +11912,11 @@ xref_tag_1 (enum tag_types tag_code, tree name,
       gcc_unreachable ();
     }
 
+  if (orig_scope == ts_lambda)
+    scope = ts_current;
+  else
+    scope = orig_scope;
+
   /* In case of anonymous name, xref_tag is only called to
      make type node and push name.  Name lookup is not required.  */
   if (ANON_AGGRNAME_P (name))
@@ -11984,6 +11990,10 @@ xref_tag_1 (enum tag_types tag_code, tree name,
 	{
 	  t = make_class_type (code);
 	  TYPE_CONTEXT (t) = context;
+	  if (orig_scope == ts_lambda)
+	    /* Remember that we're declaring a lambda to avoid bogus errors
+	       in push_template_decl.  */
+	    CLASSTYPE_LAMBDA_EXPR (t) = error_mark_node;
 	  t = pushtag (name, t, scope);
 	}
     }

gcc/cp/name-lookup.h

@@ -132,10 +132,11 @@ typedef enum tag_scope {
   ts_global = 1,	/* All scopes.  This is the 3.4.1
 			   [basic.lookup.unqual] lookup mentioned
 			   in [basic.lookup.elab]/2.  */
-  ts_within_enclosing_non_class = 2	/* Search within enclosing non-class
+  ts_within_enclosing_non_class = 2,	/* Search within enclosing non-class
 					   only, for friend class lookup
 					   according to [namespace.memdef]/3
 					   and [class.friend]/9.  */
+  ts_lambda = 3			/* Declaring a lambda closure.  */
 } tag_scope;
 
 typedef struct GTY(()) cp_class_binding {

gcc/cp/pt.c

@@ -4306,6 +4306,13 @@ check_default_tmpl_args (tree decl, tree parms, bool is_primary,
        local scope.  */
     return true;
 
+  if (TREE_CODE (decl) == TYPE_DECL
+      && TREE_TYPE (decl)
+      && LAMBDA_TYPE_P (TREE_TYPE (decl)))
+    /* A lambda doesn't have an explicit declaration; don't complain
+       about the parms of the enclosing class.  */
+    return true;
+
   if (current_class_type
       && !TYPE_BEING_DEFINED (current_class_type)
       && DECL_LANG_SPECIFIC (decl)
@@ -4674,6 +4681,8 @@ push_template_decl_real (tree decl, bool is_friend)
   if (!ctx
       || TREE_CODE (ctx) == FUNCTION_DECL
       || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
+      || (TREE_CODE (decl) == TYPE_DECL
+	  && LAMBDA_TYPE_P (TREE_TYPE (decl)))
       || (is_friend && !DECL_TEMPLATE_INFO (decl)))
     {
       if (DECL_LANG_SPECIFIC (decl)

gcc/cp/semantics.c

@@ -8984,7 +8984,7 @@ begin_lambda_type (tree lambda)
     /* Create the new RECORD_TYPE for this lambda.  */
     type = xref_tag (/*tag_code=*/record_type,
                      name,
-                     /*scope=*/ts_within_enclosing_non_class,
+                     /*scope=*/ts_lambda,
                      /*template_header_p=*/false);
   }
 

gcc/cp/tree.c

@@ -2028,11 +2028,12 @@ no_linkage_check (tree t, bool relaxed_p)
       if (TYPE_PTRMEMFUNC_P (t))
 	goto ptrmem;
       /* Lambda types that don't have mangling scope have no linkage.  We
-	 check CLASSTYPE_LAMBDA_EXPR here rather than LAMBDA_TYPE_P because
+	 check CLASSTYPE_LAMBDA_EXPR for error_mark_node because
 	 when we get here from pushtag none of the lambda information is
 	 set up yet, so we want to assume that the lambda has linkage and
 	 fix it up later if not.  */
       if (CLASSTYPE_LAMBDA_EXPR (t)
+	  && CLASSTYPE_LAMBDA_EXPR (t) != error_mark_node
 	  && LAMBDA_TYPE_EXTRA_SCOPE (t) == NULL_TREE)
 	return t;
       /* Fall through.  */

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-defarg4.C

@@ -0,0 +1,8 @@
+// PR c++/54764
+// { dg-require-effective-target c++11 }
+
+template<class T = void>
+struct c
+{
+  int (*f)(int) = [](int i){return i + i;};
+};

gcc/testsuite/g++.dg/cpp0x/lambda/lambda-nsdmi3.C

@@ -0,0 +1,9 @@
+// PR c++/55972
+// { dg-do compile { target c++11 } }
+
+class C
+{
+  void f();
+  int j = 10;
+  int i = [this]() { return this->j; }();
+};