This is the mail archive of the
gdb-patches@sources.redhat.com
mailing list for the GDB project.
Re: Fix various default.exp failures
- From: Fernando Nasser <fnasser at redhat dot com>
- To: law at redhat dot com
- Cc: gdb-patches at sources dot redhat dot com
- Date: Thu, 20 Dec 2001 12:36:18 -0500
- Subject: Re: Fix various default.exp failures
- Organization: Red Hat Canada
- References: <25873.1008868031@porcupine.cygnus.com>
You can check this in as an obvious fix.
Fernando
law@redhat.com wrote:
>
> default.exp has been intermittently failing on my HPs. Not surprisingly the
> problem is we're using uninitialized memory.
>
> In my case, the problems show up (sometimes) when a "info set" command
> is issued. Typically, the problem shows up when we get to the
> "remotelogfile" entry in the set/show command list.
>
> Basically we never initialize the "pre_show_hook" field in the cmd_list_element
> structure for new commands we create via add_set_cmd.
>
> Usually the value is zero and all is well, but sometimes the pre_show_hook
> is nonzero (ie garbage). Consider this code in do_setshow_command and what
> happens if pre_show_hook is a nonzero garbage value:
>
> /* Possibly call the pre hook. */
> if (c->pre_show_hook)
> (c->pre_show_hook) (c);
>
> Yup, we make an indirect call to some unpredictable location which usually
> results in a segfault.
>
> The fix is trivial. Initialize the pre_show_hook when we add the new command.
>
> * cli/cli-decode.c (add_cmd): Initialize pre_show_hook in
> the new command.
>
> Index: cli/cli-decode.c
> ===================================================================
> RCS file: /cvs/cvsfiles/devo/gdb/cli/cli-decode.c,v
> retrieving revision 1.5
> diff -c -3 -p -r1.5 cli-decode.c
> *** cli-decode.c 2001/10/01 01:42:05 1.5
> --- cli-decode.c 2001/12/20 17:06:22
> *************** add_cmd (char *name, enum command_class
> *** 90,95 ****
> --- 90,96 ----
> c->doc = doc;
> c->flags = 0;
> c->replacement = NULL;
> + c->pre_show_hook = NULL;
> c->hook_pre = NULL;
> c->hook_post = NULL;
> c->hook_in = 0;
--
Fernando Nasser
Red Hat Canada Ltd. E-Mail: fnasser@redhat.com
2323 Yonge Street, Suite #300
Toronto, Ontario M4P 2C9