Fix bug reported by Thomas Petazzoni <thomas.petazzoni@free-electrons.com>:

See: http://sourceware.org/ml/crossgcc/2009-05/msg00055.html

     https://bugzilla.redhat.com/show_bug.cgi?id=436037

Fix from: http://cvs.fedoraproject.org/viewvc/devel/gdb/gdb-6.8-bz436037-reg-no-longer-active.patch?revision=1.1

diff -d -urpN src.0/gdb/valops.c src.1/gdb/valops.c

--- src.0/gdb/valops.c	2008-07-27 04:00:03.000000000 +0200

+++ src.1/gdb/valops.c	2008-07-31 15:17:42.000000000 +0200

@@ -813,10 +813,18 @@ value_assign (struct value *toval, struc

 	struct frame_info *frame;

 	int value_reg;

-	/* Figure out which frame this is in currently.  */

-	frame = frame_find_by_id (VALUE_FRAME_ID (toval));

 	value_reg = VALUE_REGNUM (toval);

+	/* Figure out which frame this is in currently.  */

+	frame = frame_find_by_id (VALUE_FRAME_ID (toval));

+	/* "set $reg+=1" should work on programs with no debug info,

+	   but frame_find_by_id returns NULL here (RH bug 436037).

+	   Use current frame, it represents CPU state in this case.

+	   If frame_find_by_id is changed to do it internally

+	   (it is contemplated there), remove this.  */

+	if (!frame)

+	  frame = get_current_frame ();

+	/* Probably never happens.  */

 	if (!frame)

 	  error (_("Value being assigned to is no longer active."));