Patch for better diagnostic (was: Re: Bug in MI?)

[Manfred Hollstein]

On Fri, 6 March 1998, 10:27:21, manfred@s-direktnet.de wrote:

 > According  to  C++WP 10.3 [class.virtual],   the  `final overrider' is
 > missing, hence the program is ill-formed!
 > 
 > But, gcc's error message is IMHO absolutely misleading.

How about this patch?

BTW, how about adding references to the language definition?
IMHO, a `see [10.3 class.virtual]' would have helped me a lot ;-)

Fri Mar  6 11:05:03 1998  Manfred Hollstein  <manfred@s-direktnet.de>

	* typeck2.c (abstract_virtuals_error): Give a better
	diagnostic for the special case `virtual base classes'.

diff -up egcs-1.0.2.orig/gcc/cp/typeck2.c egcs-1.0.2/gcc/cp/typeck2.c
--- egcs-1.0.2.orig/gcc/cp/typeck2.c	Thu Nov 27 07:47:02 1997
+++ egcs-1.0.2/gcc/cp/typeck2.c	Thu Nov 27 07:47:02 1997
@@ -155,7 +155,14 @@ abstract_virtuals_error (decl, type)
   /* Only go through this once.  */
   if (TREE_PURPOSE (u) == NULL_TREE)
     {
-      error ("  since the following virtual functions are abstract:");
+      /* In class.c:override_one_vtable we might have marked this as a
+	 class with abstract methods; in fact, it is a class with
+	 virtual base classes for which not all virtual methods
+	 have been overridden.  */
+      if (u == error_mark_node)
+	error ("  since the following virtual functions are not finally overridden:");
+      else
+	error ("  since the following virtual functions are abstract:");
       TREE_PURPOSE (u) = error_mark_node;
       while (u)
 	{
@@ -163,7 +170,13 @@ abstract_virtuals_error (decl, type)
 	  u = TREE_CHAIN (u);
 	}
     }
-  else cp_error ("  since type `%T' has abstract virtual functions", type);
+  else
+    {
+      if (u == error_mark_node)
+	cp_error ("  since type `%T' has virtual functions", type);
+      else
+	cp_error ("  since type `%T' has abstract virtual functions", type);
+    }
 }
 
 /* Print an error message for invalid use of a signature type.