Re: cli/2451: user-defined commands fail when testing for structure members that don't exist

Re: cli/2451: user-defined commands fail when testing for structure members that don't exist

[Daniel Jacobowitz]

The following reply was made to PR cli/2451; it has been noted by GNATS.

From: Daniel Jacobowitz <drow@false.org>
To: emf1123@gmail.com
Cc: gdb-gnats@sourceware.org
Subject: Re: cli/2451: user-defined commands fail when testing for
	structure members that don't exist
Date: Fri, 2 May 2008 12:36:15 -0400

 On Fri, May 02, 2008 at 03:33:09PM -0000, emf1123@gmail.com wrote:
 > define mumble
 >  if $arg0->container->value
 >    print $arg0->container->value
 >  else
 >    print $arg0->value
 >  end
 > end
 > 
 > then "mumble foo" fails if foo->container doesn't exist.
 
 Yes, unfortunately the CLI has no "try" construct and no way to do
 logic on types.  The Python scripting we're currently working on
 will obviously not have this limitation :-)
 
 -- 
 Daniel Jacobowitz
 CodeSourcery

cli/2451: user-defined commands fail when testing for structure members that don't exist

[emf1123]

>Number:         2451
>Category:       cli
>Synopsis:       user-defined commands fail when testing for structure members that don't exist
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Fri May 02 15:38:01 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     emf1123@gmail.com
>Release:        gdb-6.8
>Organization:
>Environment:

>Description:
when debugging a program with singleton and polymorphic container data structures, you end up with variables similar to:
foo->container->value  *OR* foo->value.  

a user macro such as:

define mumble
 if $arg0->container->value
   print $arg0->container->value
 else
   print $arg0->value
 end
end

then "mumble foo" fails if foo->container doesn't exist.

>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: