[patch] Fix PR c++/28111: ICE with invalid friend in template class

[Volker Reichelt]

The C++ frontend ICEs on the following invalid code snippet:

  template<typename> void foo();

  template<typename T> struct A
  {
      friend void foo<>(typename T::X);
  };

  A<int> a;

bug.cc: In instantiation of 'A<int>':
bug.cc:8:   instantiated from here
bug.cc:5: error: 'int' is not a class, struct, or union type
bug.cc:5: internal compiler error: tree check: expected function_type or method_type, have error_mark in determine_specialization, at cp/pt.c:1396
Please submit a full bug report, [etc.]

We already have a sanity check at the beginning of determine_specialization.
But it only checks the first argument and not the seocond for
error_mark_nodes. The patch fixes the ICE by also checking the
second argument.

Bootstrapped and regtested on x86_64-unknown-linux-gnu.
Ok for mainline?

Regards,
Volker

:ADDPATCH C++:


2006-06-21  Volker Reichelt  <reichelt@igpm.rwth-aachen.de>

	PR c++/28111
	* pt.c (determine_specialization): Check for invalid decls.

===================================================================
--- gcc/gcc/cp/pt.c	(revision 114800)
+++ gcc/gcc/cp/pt.c	(working copy)
@@ -1354,7 +1354,7 @@ determine_specialization (tree template_id,
 
   *targs_out = NULL_TREE;
 
-  if (template_id == error_mark_node)
+  if (template_id == error_mark_node || decl == error_mark_node)
     return error_mark_node;
 
   fns = TREE_OPERAND (template_id, 0);
===================================================================

2006-06-21  Volker Reichelt  <reichelt@igpm.rwth-aachen.de>

	PR c++/28111
	* g++.dg/template/friend43.C: New test.

===================================================================
--- gcc/gcc/testsuite/g++.dg/template/friend43.C	2005-08-29 00:25:44 +0200
+++ gcc/gcc/testsuite/g++.dg/template/friend43.C	2006-06-20 18:54:35 +0200
@@ -0,0 +1,11 @@
+// PR c++/28111
+// { dg-do compile }
+
+template<typename> void foo();
+
+template<typename T> struct A
+{
+  friend void foo<>(typename T::X);  // { dg-error "not a class" }
+};
+
+A<int> a;
===================================================================