missed uninitialised variable warning

[Michael Matz]

Hi,

On 4 Aug 2003, Alexandre Oliva wrote:

> > That's a feature.
>
> Not really.  At some point I thought it was, and even argued for it,

I darkly remember.

> but then I was convinced with hard data that it was just a bug that
> I'd happened to take for a feature,

I don't remember this, though.

> and that it was actually undesirable, but hard to fix.

Hmm, hard to fix ...  I don't know, the patch below does it for the easy
'x = x' case.  But I immediately withdraw it, as I like this feature ;-)


Ciao,
Michael.
Index: function.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/function.c,v
retrieving revision 1.449
diff -u -p -r1.449 function.c
--- function.c	25 Jul 2003 09:52:25 -0000	1.449
+++ function.c	4 Aug 2003 13:05:23 -0000
@@ -5566,7 +5566,7 @@ uninitialized_vars_warning (tree block)

 	     We do not care about the actual value in DECL_INITIAL, so we do
 	     not worry that it may be a dangling pointer.  */
-	  && DECL_INITIAL (decl) == NULL_TREE
+	  && (DECL_INITIAL (decl) == NULL_TREE || DECL_INITIAL (decl) == decl)
 	  && regno_uninitialized (REGNO (DECL_RTL (decl))))
 	warning ("%H'%D' might be used uninitialized in this function",
                  &DECL_SOURCE_LOCATION (decl), decl);