Fix candidate for PR c++/43206

gcc/cp/ChangeLog:
	PR c++/43206
	* cp-tree.h (get_template_parms_at_level): Declare ...
	* pt.c (get_template_parms_at_level): ... new function.
	* typeck.c (get_template_parms_of_dependent_type): If a template
	type parm's DECL_CONTEXT isn't yet set, get its siblings from
	current_template_parms. Use get_template_parms_at_level. Remove
	useless test.
	(incompatible_dependent_types_p): If we get empty parms from just one
	of the template type parms we are comparing then the template parms are
	incompatible.

gcc/testsuite/ChangeLog:
	PR c++/43206
	* g++.dg/template/typedef30.C: New test case.

From-SVN: r157730

gcc/cp/ChangeLog

@@ -1,3 +1,16 @@
+2010-03-25  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/43206
+	* cp-tree.h (get_template_parms_at_level): Declare ...
+	* pt.c (get_template_parms_at_level): ... new function.
+	* typeck.c (get_template_parms_of_dependent_type): If a template
+	type parm's DECL_CONTEXT isn't yet set, get its siblings from
+	current_template_parms. Use get_template_parms_at_level. Remove
+	useless test.
+	(incompatible_dependent_types_p): If we get empty parms from just one
+	of the template type parms we are comparing then the template parms are
+	incompatible.
+
 2010-03-24  Jason Merrill  <jason@redhat.com>
 
 	PR c++/43502

gcc/cp/cp-tree.h

@@ -4973,6 +4973,7 @@ extern void init_template_processing		(void);
 bool template_template_parameter_p		(const_tree);
 extern bool primary_template_instantiation_p    (const_tree);
 extern tree get_primary_template_innermost_parameters	(const_tree);
+extern tree get_template_parms_at_level (tree, unsigned);
 extern tree get_template_innermost_arguments	(const_tree);
 extern tree get_template_argument_pack_elems	(const_tree);
 extern tree get_function_template_decl		(const_tree);

gcc/cp/pt.c

@@ -2839,6 +2839,25 @@ get_primary_template_innermost_parameters (const_tree t)
   return parms;
 }
 
+/* Return the template parameters of the LEVELth level from the full list
+   of template parameters PARMS.  */
+
+tree
+get_template_parms_at_level (tree parms, unsigned level)
+{
+  tree p;
+  if (!parms
+      || TREE_CODE (parms) != TREE_LIST
+      || level > TMPL_PARMS_DEPTH (parms))
+    return NULL_TREE;
+
+  for (p = parms; p; p = TREE_CHAIN (p))
+    if (TMPL_PARMS_DEPTH (p) == level)
+      return p;
+
+  return NULL_TREE;
+}
+
 /* Returns the template arguments of T if T is a template instantiation,
    NULL otherwise.  */
 

gcc/cp/typeck.c

@@ -1113,9 +1113,17 @@ get_template_parms_of_dependent_type (tree t)
   /* If T1 is a typedef or whatever has a template info associated
      to its context, get the template parameters from that context.  */
   else if (typedef_variant_p (t)
-      && DECL_CONTEXT (TYPE_NAME (t))
-      && !NAMESPACE_SCOPE_P (TYPE_NAME (t)))
+	   && !NAMESPACE_SCOPE_P (TYPE_NAME (t)))
     tinfo = get_template_info (DECL_CONTEXT (TYPE_NAME (t)));
+  else if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
+	   && DECL_CONTEXT (TYPE_NAME (t)) == NULL_TREE)
+    /* We have not yet created the DECL_TEMPLATE this
+       template type parm belongs to. It probably means
+       that we are in the middle of parsing the template parameters
+       of a template, and T is one of the parameters we have parsed.
+       Let's return the list of template parms we have parsed so far.  */
+    return get_template_parms_at_level (current_template_parms,
+					TEMPLATE_TYPE_LEVEL (t));
   else if (TYPE_CONTEXT (t)
 	   && !NAMESPACE_SCOPE_P (t))
     tinfo = get_template_info (TYPE_CONTEXT (t));
@@ -1170,6 +1178,17 @@ incompatible_dependent_types_p (tree t1, tree t2)
   tparms1 = get_template_parms_of_dependent_type (t1);
   tparms2 = get_template_parms_of_dependent_type (t2);
 
+  /* If T2 is a template type parm and if we could not get the template
+     parms it belongs to, that means we have not finished parsing the
+     full set of template parameters of the template declaration it
+     belongs to yet. If we could get the template parms T1 belongs to,
+     that mostly means T1 and T2 belongs to templates that are
+     different and incompatible.  */
+  if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM
+      && (tparms1 == NULL_TREE || tparms2 == NULL_TREE)
+      && tparms1 != tparms2)
+    return true;
+
   if (tparms1 == NULL_TREE
       || tparms2 == NULL_TREE
       || tparms1 == tparms2)

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2010-03-25  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/43206
+	* g++.dg/template/typedef30.C: New test case.
+
 2010-03-25  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/43385

gcc/testsuite/g++.dg/template/typedef30.C

@@ -0,0 +1,20 @@
+// Origin: PR c++/43206
+// { dg-do compile }
+
+template<class A> struct NumericTraits{ typedef A TInputImage;};
+template<class B> class CovariantVector{};
+template<class C> struct Image{ typedef C PixelType;};
+template<class H, class E, class D>
+class F {
+  typedef H G;
+  typedef
+  typename NumericTraits<typename G::PixelType>::RealType
+  InputRealType;
+};
+
+template<typename TInputImage,
+         typename TOutputImage=Image<CovariantVector<typename NumericTraits<typename TInputImage::PixelType>::TInputImage> > >
+class XXX{};
+
+XXX<Image<float> > x;
+