* mcheck.c: Avoid warning about undeclared abort fn.

* tm-sparc.h (PC_ADJUST):  Avoid calling error() from this;
it causes recursive calls to error() when used in cleanups.
To do so requires that we make it a function, so we do.
* sparc-tdep.c (sparc_pc_adjust):  New implem of PC_ADJUST.
* utils.c (do_cleanups):  Remove the current cleanup from the
chain *before* calling it, in case error() is called from it.
The result won't be pretty, but won't be an infinite loop either.

gdb/utils.c

@@ -134,8 +134,8 @@ do_cleanups (old_chain)
   register struct cleanup *ptr;
   while ((ptr = cleanup_chain) != old_chain)
     {
+      cleanup_chain = ptr->next;	/* Do this first incase recursion */
       (*ptr->function) (ptr->arg);
-      cleanup_chain = ptr->next;
       free (ptr);
     }
 }