C++ PATCH for template crash

[Mark Mitchell <mark at codesourcery dot com>]

Here's a patch for a recently reported buglet.

-- 
Mark Mitchell                   mark@codesourcery.com
CodeSourcery, LLC               http://www.codesourcery.com

1999-04-23  Mark Mitchell  <mark@codesourcery.com>

	* search.c (is_subobject_of_p): Handle TEMPLATE_TYPE_PARMs and
	such as base classes.

Index: testsuite/g++.old-deja/g++.pt/crash40.C
===================================================================
RCS file: crash40.C
diff -N crash40.C
--- /dev/null	Sat Dec  5 20:30:03 1998
+++ crash40.C	Fri Apr 23 09:38:29 1999
@@ -0,0 +1,19 @@
+// Build don't link:
+// Origin: rch@larissa.sd.bi.ruhr-uni-bochum.de
+
+template< class X >
+struct VB: public virtual X
+{};
+
+template< class MOPTerm1, class MOPTerm2 >
+struct MOPTermUnify
+{
+  struct MO:
+    public VB<MOPTerm1>,
+    public VB<MOPTerm2>
+  {
+    void   fix()
+      { 
+      }
+  };
+};
Index: cp/search.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/cp/search.c,v
retrieving revision 1.98
diff -u -p -r1.98 search.c
--- search.c	1999/04/20 21:48:51	1.98
+++ search.c	1999/04/23 16:39:15
@@ -1062,21 +1062,27 @@ static int
 is_subobject_of_p (parent, binfo)
      tree parent, binfo;
 {
-  tree binfos = BINFO_BASETYPES (binfo);
-  int i, n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
+  tree binfos;
+  int i, n_baselinks;
 
-  if (TREE_VIA_VIRTUAL (parent))
-    parent = TYPE_BINFO (TREE_TYPE (parent));
-  if (TREE_VIA_VIRTUAL (binfo))
-    binfo = TYPE_BINFO (TREE_TYPE (binfo));
+  parent = canonical_binfo (parent);
+  binfo = canonical_binfo (binfo);
 
   if (parent == binfo)
     return 1;
 
+  binfos = BINFO_BASETYPES (binfo);
+  n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
+
   /* Process and/or queue base types.  */
   for (i = 0; i < n_baselinks; i++)
     {
-      tree base_binfo = canonical_binfo (TREE_VEC_ELT (binfos, i));
+      tree base_binfo = TREE_VEC_ELT (binfos, i);
+      if (!CLASS_TYPE_P (TREE_TYPE (base_binfo)))
+	/* If we see a TEMPLATE_TYPE_PARM, or some such, as a base
+	   class there's no way to descend into it.  */
+	continue;
+
       if (is_subobject_of_p (parent, base_binfo))
 	return 1;
     }