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To: Vladimir Prus <vladimir@codesourcery.com>
Cc: gdb-patches@sources.redhat.com
Subject: Re: [RFA] Don't reset watchpoint block on solib load.
References: <200711202013.47537.vladimir@codesourcery.com> 	<m3abozfg5c.fsf@codesourcery.com> 	<200711290955.46751.vladimir@codesourcery.com>
From: Jim Blandy <jimb@codesourcery.com>
Date: Thu, 29 Nov 2007 18:40:00 -0000
In-Reply-To: <200711290955.46751.vladimir@codesourcery.com> (Vladimir Prus's message of "Thu, 29 Nov 2007 09:55:46 +0300")
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Vladimir Prus <vladimir at codesourcery.com> writes:
> On Wednesday 28 November 2007 02:00:15 Jim Blandy wrote:
>
>> We also call breakpoint_re_set_one when we've unloaded a shared
>> library.  
>
> Can you point me at a codepath that would cause breakpoint_re_set_one
> to be called when a shared library is *unloaded*? I've poked at
> this for a while, and can't see it.

I beg your pardon.  It does not.  This is a pretty serious bug.  A
dlclose will call free_objfile:

handle_inferior_event
-> solib_add
   -> update_solib_list
      -> free_objfile

but it takes no steps to clear references to the freed shared
library's symbols.  I had assumed that it must be calling
clear_symtab_users.  We need to call clear_symtab_users whenever any
objfile is freed.

Now, where to do this...