[Ace-users] [tao-bugs] Crash in TAO_ORB_Core_Static_Resources::instance()

[Johnny Willemsen]

Hi JT,

Thanks for using the PRF form. Can you make a small reproducer, report the
problem in bugzilla and then put the test in svn with the given bugzilla
number. 

Regards,

Johnny Willemsen
Remedy IT
Postbus 101
2650 AC  Berkel en Rodenrijs
The Netherlands
www.theaceorb.nl / www.remedy.nl  

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> -----Original Message-----
> From: tao-bugs-bounces at cse.wustl.edu 
> [mailto:tao-bugs-bounces at cse.wustl.edu] On Behalf Of J.T. Conklin
> Sent: Thursday, November 01, 2007 12:34 AM
> To: tao-bugs at cs.wustl.edu
> Subject: [tao-bugs] Crash in TAO_ORB_Core_Static_Resources::instance()
> 
> 
>     TAO VERSION: 1.6.1 (2007-10-29 svn snapshot)
>     ACE VERSION: 5.6.1
> 
>     HOST MACHINE and OPERATING SYSTEM:
> 
> NetBSD orac.acorntoolworks.com 3.0_STABLE NetBSD 3.0_STABLE 
> (ORAC) #0: Tue Feb 21 20:05:51 PST 2006  
> jtc at orac.acorntoolworks.com:/home/jtc/netbsd/NetBSD-3/src/sys/
> arch/i386/compile/ORAC i386
> 
>     TARGET MACHINE and OPERATING SYSTEM, if different from HOST:
> 
> NetBSD orac.acorntoolworks.com 3.0_STABLE NetBSD 3.0_STABLE 
> (ORAC) #0: Tue Feb 21 20:05:51 PST 2006  
> jtc at orac.acorntoolworks.com:/home/jtc/netbsd/NetBSD-3/src/sys/
> arch/i386/compile/ORAC i386
> 
>     COMPILER NAME AND VERSION (AND PATCHLEVEL):
> 
> gcc version 3.3.3 (NetBSD nb3 20040520)
> 
>     THE $ACE_ROOT/ace/config.h FILE [if you use a link to a platform-
>     specific file, simply state which one]:
> 
> config-netbsd.h
> 
>     THE $ACE_ROOT/include/makeinclude/platform_macros.GNU FILE [if you
>     use a link to a platform-specific file, simply state which one
>     (unless this isn't used in this case, e.g., with Microsoft Visual
>     C++)]:
> 
> platform_netbsd.GNU
> 
>     CONTENTS OF 
> $ACE_ROOT/bin/MakeProjectCreator/config/default.features
>     (used by MPC when you generate your own makefiles):
> 
> N/A
> 
>     AREA/CLASS/EXAMPLE AFFECTED:
> 
> TAO_ORB_Core_Static_Resources::instance()
> 
>     DOES THE PROBLEM AFFECT:
>         EXECUTION
> 
>     SYNOPSIS:
> 
> Core dump in TAO_ORB_Core_Static_Resources::instance()
> 
>     DESCRIPTION:
> 
> While the TAO unit tests look pretty good on my platform, many of my 
> own applications dump core in a static constructor when initializing 
> TAO_ORB_Core_Static_Resources::initialization_reference_ via the 
> TAO_ORB_Core_Static_Resources::instance() factory method.
> 
>     TAO_ORB_Core_Static_Resources*
>     TAO_ORB_Core_Static_Resources::instance (void)
>     {
>       ACE_Service_Gestalt *current = ACE_Service_Config::current();
>       TAO_ORB_Core_Static_Resources* tocsr =
> 	ACE_Dynamic_Service<TAO_ORB_Core_Static_Resources>::instance
> 	(current,"TAO_ORB_Core_Static_Resources",true);
> 
>       if (tocsr == 0)
> 	{
> 	  // This new is never freed on purpose.  The data specified by
> 	  // it needs to be around for the last shared library 
> that references
> 	  // this class.  This could occur in a destructor in a 
> shared library
> 	  // that is unloaded after this one.  One solution to 
> avoid this
> 	  // harmless memory leak would be to use reference counting.
> 	  
> current->process_directive(ace_svc_desc_TAO_ORB_Core_Static_Re
sources);
> 	  tocsr = 
> ACE_Dynamic_Service<TAO_ORB_Core_Static_Resources>::instance
> 	    (current,"TAO_ORB_Core_Static_Resources",true);
> 
> 	  ACE_Service_Gestalt *global = ACE_Service_Config::global();
> 	  if (current != global)
> 	    {
> 	      TAO_ORB_Core_Static_Resources* global_tocsr =
> 		
> ACE_Dynamic_Service<TAO_ORB_Core_Static_Resources>::instance
> 		(global,"TAO_ORB_Core_Static_Resources");
> 	      *tocsr = *global_tocsr;
> 	    }
> 	}
> 
>       //  return TAO_ORB_Core_Static_Resources::instance_;
>       return tocsr;
>     }
> 
> The crash occurs in the "*tocsr = *global_tocsr" assignment.  
> It appears 
> that instance() method has been called on a non-global 
> gestalt before it
> was called on the global one.  So global_tocsr is null, and 
> the assignment
> fails when the fields are copied.
> 
> I'm not familiar with the new gestalt code, so I don't know whether an
> invarient that requires that the global gestalt be initialized first
> is being violated, or whether the ctor initialization order has
> exposed a bug.  I'm also not clear to me what the purpose of the local
> tocsr being initialized from the global_tocsr.  I forced to guess, I'd
> say the intent is for the global one to be initialized first, possibly
> modified, and ->process_directive() is called to create the 
> gestalt, but 
> the intent is to overwrite it.  But even that seems to assume ordering
> of the initial creation of the global_toscr, it's initialization, and
> the creation of "current" toscr's that doesn't seem manifest 
> in the code.
> But like I said, I'm not familiar with the gestalt code.
> 
>     REPEAT BY:
> 
> No test case yet.
> 
>     SAMPLE FIX/WORKAROUND:
> 
> -- 
> J.T. Conklin
> 
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