C++ PATCH for c++/65879 (error on member function of nested class of anonymous class)

[Jason Merrill]

It doesn't make sense to complain about a function using its own 
enclosing class.  There were two problems here:

1) The function should have been marked as internal because its class is 
internal.
2) We shouldn't bother looking at 'this' for no-linkage types.
Tested x86_64-pc-linux-gnu, applying to trunk.  Applying #2 to 5 and 4.9 
as well.
commit 6ad33315431b2e6dc2664a36f0a3b308a9eafd40
Author: Jason Merrill <ja...@redhat.com>
Date:   Mon Jun 22 16:07:13 2015 -0400

    	PR c++/65879
    	* decl.c (grokfndecl): Check the linkage of ctype, not just
    	TYPE_ANONYMOUS_P.
    	* tree.c (no_linkage_check): Skip the 'this' pointer.

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index d14ffe2..a8fc1a5 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -7794,7 +7794,7 @@ grokfndecl (tree ctype,
 
   /* Members of anonymous types and local classes have no linkage; make
      them internal.  If a typedef is made later, this will be changed.  */
-  if (ctype && (TYPE_ANONYMOUS_P (ctype)
+  if (ctype && (!TREE_PUBLIC (TYPE_MAIN_DECL (ctype))
 		|| decl_function_context (TYPE_MAIN_DECL (ctype))))
     publicp = 0;
 
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index a9c9214..bc8428d 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -2299,14 +2299,14 @@ no_linkage_check (tree t, bool relaxed_p)
       return no_linkage_check (TYPE_PTRMEM_CLASS_TYPE (t), relaxed_p);
 
     case METHOD_TYPE:
-      r = no_linkage_check (TYPE_METHOD_BASETYPE (t), relaxed_p);
-      if (r)
-	return r;
-      /* Fall through.  */
     case FUNCTION_TYPE:
       {
-	tree parm;
-	for (parm = TYPE_ARG_TYPES (t);
+	tree parm = TYPE_ARG_TYPES (t);
+	if (TREE_CODE (t) == METHOD_TYPE)
+	  /* The 'this' pointer isn't interesting; a method has the same
+	     linkage (or lack thereof) as its enclosing class.  */
+	  parm = TREE_CHAIN (parm);
+	for (;
 	     parm && parm != void_list_node;
 	     parm = TREE_CHAIN (parm))
 	  {
diff --git a/gcc/testsuite/g++.dg/abi/anon2.C b/gcc/testsuite/g++.dg/abi/anon2.C
index cee9237..396edd3 100644
--- a/gcc/testsuite/g++.dg/abi/anon2.C
+++ b/gcc/testsuite/g++.dg/abi/anon2.C
@@ -23,9 +23,9 @@ namespace N2 {
     typedef struct { } B;
     struct C {
       // { dg-final { scan-assembler-not ".weak\(_definition\)?\[ \t\]_?_ZN2N23._31C3fn1ENS0_1BE" { target c++11 } } }
-      static void fn1 (B) { } // { dg-error "no linkage" "" { target { ! c++11 } } }
+      static void fn1 (B) { }
       // { dg-final { scan-assembler-not ".weak\(_definition\)?\[ \t\]_?_ZN2N23._31C3fn2ES1_" { target c++11 } } }
-      static void fn2 (C) { } // { dg-error "no linkage" "" { target { ! c++11 } } }
+      static void fn2 (C) { }
     };
   } const D;
 
diff --git a/gcc/testsuite/g++.dg/other/anon7.C b/gcc/testsuite/g++.dg/other/anon7.C
new file mode 100644
index 0000000..12c1ab2
--- /dev/null
+++ b/gcc/testsuite/g++.dg/other/anon7.C
@@ -0,0 +1,10 @@
+// PR c++/65879
+
+static struct
+{
+  void f();
+  struct Inner
+  {
+    void g();
+  };
+} x;