Re: c++/2366: gdb crash: infinite recursion in fill_in_vptr_fieldno

Re: c++/2366: gdb crash: infinite recursion in fill_in_vptr_fieldno

[Daniel Jacobowitz]

The following reply was made to PR c++/2366; it has been noted by GNATS.

From: Daniel Jacobowitz <drow@false.org>
To: aristovski@qnx.com
Cc: gdb-gnats@sources.redhat.com, rmansfield@qnx.com
Subject: Re: c++/2366: gdb crash: infinite recursion in fill_in_vptr_fieldno
Date: Wed, 21 Nov 2007 11:57:13 -0500

 On Wed, Nov 21, 2007 at 04:39:02PM -0000, aristovski@qnx.com wrote:
 > >Release:        unknown-1.0
 
 What version of GDB?  Have you tried the latest?
 
 -- 
 Daniel Jacobowitz
 CodeSourcery

c++/2366: gdb crash: infinite recursion in fill_in_vptr_fieldno

[aristovski]

>Number:         2366
>Category:       c++
>Synopsis:       gdb crash: infinite recursion in fill_in_vptr_fieldno
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Wed Nov 21 16:48:01 UTC 2007
>Closed-Date:
>Last-Modified:
>Originator:     aristovski@qnx.com
>Release:        unknown-1.0
>Organization:
>Environment:

>Description:
GDB crashes when accesing type information. It runs into an infinite recursion in fill_in_vptr_fieldno.

The crash occurs with gcc versions (only versions we used are listed)
4.0.3
3.4.x
3.3.x

It has to do with namespaces and wrong resolution of a base class. In short:
namespace N1 {
class A {};
}
namespace N2 {
class B : public N1::A {}
}

When printing "this" when in B's method, it resolves base class to be B again.

See attached project with sources and test case (and gdb command file).
>How-To-Repeat:
Use attached project and command file:

gdb
(gdb) source crash.source

>Fix:

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