🚀 go-pugleaf

Symptom:
	On COFF systems, gdb 3.? (2,3 certainly) drops core under varied
	circumstances, at some point in time after looking for a
	symbol table in an executable that lacks one..

Cause:
	symbol-file-command in coffread.c adds cleanup records which include 
	a pointer to a pointer residing in it's own stack frame. When 
	this routine finds that there are no symbols, it returns to it's
	caller, leaving those cleanups unprocessed.  At some point in
	the future they WILL be processed, but not before the pointer
	(residing on the stack) get overwritten. When free_current_contents
	is called from do_cleanups, indirecting through this pointer
	kills gdb.

Fix:
	Don't leave those cleanups hanging around after exiting the frame:

*** coffread.c.dist	Wed Aug 23 09:31:55 1989
--- coffread.c	Sat Nov  4 00:29:35 1989
***************
*** 749,754 ****
--- 749,755 ----
        free_all_symtabs ();
        printf ("%s does not have a symbol-table.\n", name);
        fflush (stdout);
+       do_cleanups (old_chain);
        return;
      }