typeck.c (get_member_function_from_ptrfunc): Always consider virtuality inside member pointer.

	* typeck.c (get_member_function_from_ptrfunc): Always consider
	virtuality inside member pointer.

From-SVN: r29494

gcc/cp/ChangeLog

+1999-09-18  Martin von Loewis  <loewis@informatik.hu-berlin.de>
+
+	* typeck.c (get_member_function_from_ptrfunc): Always consider
+	virtuality inside member pointer.
+
 1999-09-17  Mark Mitchell  <mark@codesourcery.com>
 
         Turn on function-at-a-time processing.  

gcc/cp/typeck.c

@@ -2821,13 +2821,13 @@ get_member_function_from_ptrfunc (instance_ptrptr, function)
 					       NULL_TREE, 0));
       e3 = PFN_FROM_PTRMEMFUNC (function);
 
-      if (TYPE_SIZE (basetype) != NULL_TREE
-	  && ! TYPE_VIRTUAL_P (basetype))
-	/* If basetype doesn't have virtual functions, don't emit code to
-	   handle that case.  */
-	e1 = e3;
-      else
-	{
+      /* This used to avoid checking for virtual functions if basetype
+	 has no virtual functions, according to an earlier ANSI draft.
+	 With the final ISO C++ rules, such an optimization is
+	 incorrect: A pointer to a derived member can be static_cast
+	 to pointer-to-base-member, as long as the dynamic object
+	 later has the right member. */
+
       /* Promoting idx before saving it improves performance on RISC
 	 targets.  Without promoting, the first compare used
 	 load-with-sign-extend, while the second used normal load then
@@ -2880,7 +2880,6 @@ get_member_function_from_ptrfunc (instance_ptrptr, function)
       if (TREE_CODE (instance_ptr) == SAVE_EXPR)
 	e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
 		    instance_ptr, e1);
-	}
 
       *instance_ptrptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
 				instance_ptr, delta);