re PR c++/21853 (constness of pointer to data member ignored)

	PR c++/21853
	* typeck.c (casts_away_constness_r): Do not drop cv-qualifiers on
	the pointed-to type for a pointer-to-member.

	PR c++/21853
	* g++.dg/expr/static_cast6.C: New test.

From-SVN: r100560

gcc/cp/ChangeLog

 2005-06-03  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/21853
+	* typeck.c (casts_away_constness_r): Do not drop cv-qualifiers on
+	the pointed-to type for a pointer-to-member.
+
 	PR c++/21336
 	* cp-tree.h (grok_op_properties): Remove friendp parameter.
 	* decl.c (grokfndecl): Adjust call.

gcc/cp/typeck.c

@@ -6466,11 +6466,6 @@ casts_away_constness_r (tree *t1, tree *t2)
      and pointers to members (conv.qual), the "member" aspect of a
      pointer to member level is ignored when determining if a const
      cv-qualifier has been cast away.  */
-  if (TYPE_PTRMEM_P (*t1))
-    *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
-  if (TYPE_PTRMEM_P (*t2))
-    *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
-
   /* [expr.const.cast]
 
      For  two  pointer types:
@@ -6488,9 +6483,8 @@ casts_away_constness_r (tree *t1, tree *t2)
      to
 
             Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *.  */
-
-  if (TREE_CODE (*t1) != POINTER_TYPE
-      || TREE_CODE (*t2) != POINTER_TYPE)
+  if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
+      || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
     {
       *t1 = cp_build_qualified_type (void_type_node,
 				     cp_type_quals (*t1));
@@ -6501,8 +6495,16 @@ casts_away_constness_r (tree *t1, tree *t2)
   
   quals1 = cp_type_quals (*t1);
   quals2 = cp_type_quals (*t2);
-  *t1 = TREE_TYPE (*t1);
-  *t2 = TREE_TYPE (*t2);
+
+  if (TYPE_PTRMEM_P (*t1))
+    *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
+  else
+    *t1 = TREE_TYPE (*t1);
+  if (TYPE_PTRMEM_P (*t2))
+    *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
+  else
+    *t2 = TREE_TYPE (*t2);
+
   casts_away_constness_r (t1, t2);
   *t1 = build_pointer_type (*t1);
   *t2 = build_pointer_type (*t2);

gcc/testsuite/ChangeLog

+2005-06-03  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/21853
+	* g++.dg/expr/static_cast6.C: New test.
+
 2005-06-03  Diego Novillo  <dnovillo@redhat.com>
 
 	* gcc.dg/tree-ssa/vrp14.c: New test.

gcc/testsuite/g++.dg/expr/static_cast6.C

+// PR c++/21853
+
+struct blah {
+  int a;
+};
+
+int main( int argc, char ** argv ) {
+  int blah::* ptdma = &blah::a;
+
+  const void *ptdmv = static_cast< void * >( &ptdma );
+
+  int blah::* const ptdmb = * static_cast< int blah::* const * >( ptdmv );
+
+  return 0;
+}