Patch to enable a fully working gdb for GNU/Hurd

[Svante Signell <svante.signell@telia.com>]

Dear list,

Here is an attempt to create a complete patch for gdb to make it run
successfully on GNU/Hurd.

Problem description:
When starting gdb the following output is written:
Can't fetch registers from thread bogus thread id 1: No such thread

This makes gdb completely unusable for debugging purposes without this
patch.

Patch size: Small change

ChangeLog:
gdb/
2011-06-29 Svante Signell <svante.signell@telia.com> 

 * gnu_nat.c: Activate prune_threads() for Hurd
 * thread.c: Make prune_threads() visible outside current scope.
 * gdbthread.h: Declare prune_threads()
 * Fix PR gdb/12222

gdb-7.2.patch
--- gdb-7.2/gdb/gnu-nat.c.orig	2010-05-14 22:17:37.000000000 +0200
+++ gdb-7.2/gdb/gnu-nat.c	2011-03-28 09:07:49.000000000 +0200
@@ -1578,8 +1578,8 @@
 	  if (--inf->pending_execs == 0)
 	    /* We're done!  */
 	    {
+	      prune_threads ();	/* Get rid of the old shell threads */
 #if 0				/* do we need this? */
-	      prune_threads (1);	/* Get rid of the old shell threads */
 	      renumber_threads (0);	/* Give our threads reasonable names. */
 #endif
 	    }
--- gdb-7.2/gdb/thread.c.orig	2010-08-06 21:51:49.000000000 +0200
+++ gdb-7.2/gdb/thread.c	2011-03-28 09:04:52.000000000 +0200
@@ -61,7 +61,6 @@
 static void info_threads_command (char *, int);
 static void thread_apply_command (char *, int);
 static void restore_current_thread (ptid_t);
-static void prune_threads (void);
 
 /* Frontend view of the thread state.  Possible extensions: stepping,
    finishing, until(ling),...  */
@@ -518,7 +517,7 @@
   return 1;
 }
 
-static void
+void
 prune_threads (void)
 {
   struct thread_info *tp, *next;
--- gdb-7.2/gdb/gdbthread.h.orig	2010-01-12 22:40:24.000000000 +0100
+++ gdb-7.2/gdb/gdbthread.h	2011-03-28 09:03:55.000000000 +0200
@@ -213,6 +213,9 @@
 /* Delete an existing thread list entry.  */
 extern void delete_thread (ptid_t);
 
+/* Prune inactive threads  */
+extern void prune_threads (void);
+
 /* Delete an existing thread list entry, and be quiet about it.  Used
    after the process this thread having belonged to having already
    exited, for example.  */