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To: Jan Kiszka <jan.kiszka@web.de>
Cc: gdb@sourceware.org
Subject: Re: container_of equivalent in gdb-python script
References: <4A2FE5AB.4060707@siemens.com> <m3prdbgbnc.fsf@fleche.redhat.com> 	<4A30133F.9000909@web.de> <20090610204201.GA17154@caradoc.them.org> 	<4A30269D.7070504@web.de>
From: Tom Tromey <tromey@redhat.com>
Reply-To: Tom Tromey <tromey@redhat.com>
Date: Wed, 10 Jun 2009 21:42:00 -0000
In-Reply-To: <4A30269D.7070504@web.de> (Jan Kiszka's message of "Wed\, 10 Jun 2009 23\:33\:17 +0200")
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>>>>> "Jan" == Jan Kiszka <jan.kiszka@web.de> writes:

Daniel> It's typical to do this the same way folks do in C: Create a null
Daniel> pointer of the right type.

Jan> You can't do that with the current upstream python interface, but the
Jan> parse_and_eval solves this nicely.

Actually, for constants you can:

(gdb) python print gdb.Value(0)
0
(gdb) python print type(gdb.Value(0))
<type 'gdb.Value'>
(gdb) python print gdb.Value(0).cast(gdb.lookup_type('char').pointer())
0x0

Whoops, this seems to be undocumented.

Tom