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* [dmj+@andrew.cmu.edu: Re: C++ debugging progress]
  2001-11-28 12:18 [dmj+@andrew.cmu.edu: Re: C++ debugging progress] Daniel Jacobowitz
@ 2001-11-21 13:26 ` Daniel Jacobowitz
  2001-11-21 15:21 ` Daniel Berlin
  1 sibling, 0 replies; 4+ messages in thread
From: Daniel Jacobowitz @ 2001-11-21 13:26 UTC (permalink / raw)
  To: libstdc++, gdb

Feh.  Meant to send this to the lists.

----- Forwarded message from Daniel Jacobowitz <dmj+@andrew.cmu.edu> -----

Date: Wed, 28 Nov 2001 15:18:19 -0500
From: Daniel Jacobowitz <dmj+@andrew.cmu.edu>
Subject: Re: C++ debugging progress
To: Jason Merrill <jason@redhat.com>

On Wed, Nov 28, 2001 at 07:40:37PM +0000, Jason Merrill wrote:
> >>>>> "Daniel" == Daniel Jacobowitz <drow@mvista.com> writes:
> 
> > On Wed, Nov 28, 2001 at 09:31:07AM +0000, Jason Merrill wrote:
> 
> >> So you're using the inheritance information in the RTTI rather than the debug
> >> info?  That seems unfortunate.  I'm not sure why you would need to worry
> >> about ordering; the debug info should tell you exactly where things are.
> >> If it doesn't, it should probably be fixed.
> 
> > In that case, the debug info absolutely needs to be fixed.
> 
> >  <1><22e>: Abbrev Number: 15 (DW_TAG_structure_type)
> >      DW_AT_sibling     : <2df>  
> >      DW_AT_name        : Left   
> >      DW_AT_byte_size   : 12     
> >      DW_AT_decl_file   : 1      
> >      DW_AT_decl_line   : 2      
> >      DW_AT_containing_type: <22e>       
> >  <2><23f>: Abbrev Number: 22 (DW_TAG_inheritance)
> >      DW_AT_type        : <56>   
> >      DW_AT_data_member_location: 2 byte block: 23 8 (DW_OP_plus_uconst: 8; )
> >      DW_AT_virtuality  : 1      (virtual)
> >      DW_AT_accessibility: 1     (public)
> 
> Yep.  Since Base is a virtual base of Left, the DW_AT_data_member_location
> here should be a complex expression telling the debugger to go through the
> vtable.  I'll get on it.

Thanks!

> I'll also change the stabs output to give the offset within the vtable
> rather than the offset of the base in a complete object; gdb will still
> need to be clever enough to know what to do with it.

<delete lots of incoherent rambling>

OK, if I'm reading this at all correctly, the offset in the baseclass
definition is assumed to be 0 for a virtual baseclass, and ignored; it
is assumed that there will be a $vb later.  So that offset slot is a
perfect place to put the information I need.  Just let me know if it is
relative to the start of the vtable or to the vtable pointer.  That'll
be enough information to do a much better job.

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer

----- End forwarded message -----

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [dmj+@andrew.cmu.edu: Re: C++ debugging progress]
  2001-11-28 12:18 [dmj+@andrew.cmu.edu: Re: C++ debugging progress] Daniel Jacobowitz
  2001-11-21 13:26 ` Daniel Jacobowitz
@ 2001-11-21 15:21 ` Daniel Berlin
  2001-11-28 12:56   ` Daniel Berlin
  1 sibling, 1 reply; 4+ messages in thread
From: Daniel Berlin @ 2001-11-21 15:21 UTC (permalink / raw)
  To: Daniel Jacobowitz; +Cc: libstdc++, gdb



On Wed, 28 Nov 2001, Daniel Jacobowitz wrote:

> Feh.  Meant to send this to the lists.
>
> ----- Forwarded message from Daniel Jacobowitz <dmj+@andrew.cmu.edu> -----
>
> Date: Wed, 28 Nov 2001 15:18:19 -0500
> From: Daniel Jacobowitz <dmj+@andrew.cmu.edu>
> Subject: Re: C++ debugging progress
> To: Jason Merrill <jason@redhat.com>
>
> On Wed, Nov 28, 2001 at 07:40:37PM +0000, Jason Merrill wrote:
> > >>>>> "Daniel" == Daniel Jacobowitz <drow@mvista.com> writes:
> >
> > > On Wed, Nov 28, 2001 at 09:31:07AM +0000, Jason Merrill wrote:
> >
> > >> So you're using the inheritance information in the RTTI rather than the debug
> > >> info?  That seems unfortunate.  I'm not sure why you would need to worry
> > >> about ordering; the debug info should tell you exactly where things are.
> > >> If it doesn't, it should probably be fixed.
> >
> > > In that case, the debug info absolutely needs to be fixed.
> >
> > >  <1><22e>: Abbrev Number: 15 (DW_TAG_structure_type)
> > >      DW_AT_sibling     : <2df>
> > >      DW_AT_name        : Left
> > >      DW_AT_byte_size   : 12
> > >      DW_AT_decl_file   : 1
> > >      DW_AT_decl_line   : 2
> > >      DW_AT_containing_type: <22e>
> > >  <2><23f>: Abbrev Number: 22 (DW_TAG_inheritance)
> > >      DW_AT_type        : <56>
> > >      DW_AT_data_member_location: 2 byte block: 23 8 (DW_OP_plus_uconst: 8; )
> > >      DW_AT_virtuality  : 1      (virtual)
> > >      DW_AT_accessibility: 1     (public)
> >
> > Yep.  Since Base is a virtual base of Left, the DW_AT_data_member_location
> > here should be a complex expression telling the debugger to go through the
> > vtable.  I'll get on it.
>
> Thanks!
The small problem may be that we may not be able to handle it in gdb,
depending on how complex it is.
--Dan


^ permalink raw reply	[flat|nested] 4+ messages in thread

* [dmj+@andrew.cmu.edu: Re: C++ debugging progress]
@ 2001-11-28 12:18 Daniel Jacobowitz
  2001-11-21 13:26 ` Daniel Jacobowitz
  2001-11-21 15:21 ` Daniel Berlin
  0 siblings, 2 replies; 4+ messages in thread
From: Daniel Jacobowitz @ 2001-11-28 12:18 UTC (permalink / raw)
  To: libstdc++, gdb

Feh.  Meant to send this to the lists.

----- Forwarded message from Daniel Jacobowitz <dmj+@andrew.cmu.edu> -----

Date: Wed, 28 Nov 2001 15:18:19 -0500
From: Daniel Jacobowitz <dmj+@andrew.cmu.edu>
Subject: Re: C++ debugging progress
To: Jason Merrill <jason@redhat.com>

On Wed, Nov 28, 2001 at 07:40:37PM +0000, Jason Merrill wrote:
> >>>>> "Daniel" == Daniel Jacobowitz <drow@mvista.com> writes:
> 
> > On Wed, Nov 28, 2001 at 09:31:07AM +0000, Jason Merrill wrote:
> 
> >> So you're using the inheritance information in the RTTI rather than the debug
> >> info?  That seems unfortunate.  I'm not sure why you would need to worry
> >> about ordering; the debug info should tell you exactly where things are.
> >> If it doesn't, it should probably be fixed.
> 
> > In that case, the debug info absolutely needs to be fixed.
> 
> >  <1><22e>: Abbrev Number: 15 (DW_TAG_structure_type)
> >      DW_AT_sibling     : <2df>  
> >      DW_AT_name        : Left   
> >      DW_AT_byte_size   : 12     
> >      DW_AT_decl_file   : 1      
> >      DW_AT_decl_line   : 2      
> >      DW_AT_containing_type: <22e>       
> >  <2><23f>: Abbrev Number: 22 (DW_TAG_inheritance)
> >      DW_AT_type        : <56>   
> >      DW_AT_data_member_location: 2 byte block: 23 8 (DW_OP_plus_uconst: 8; )
> >      DW_AT_virtuality  : 1      (virtual)
> >      DW_AT_accessibility: 1     (public)
> 
> Yep.  Since Base is a virtual base of Left, the DW_AT_data_member_location
> here should be a complex expression telling the debugger to go through the
> vtable.  I'll get on it.

Thanks!

> I'll also change the stabs output to give the offset within the vtable
> rather than the offset of the base in a complete object; gdb will still
> need to be clever enough to know what to do with it.

<delete lots of incoherent rambling>

OK, if I'm reading this at all correctly, the offset in the baseclass
definition is assumed to be 0 for a virtual baseclass, and ignored; it
is assumed that there will be a $vb later.  So that offset slot is a
perfect place to put the information I need.  Just let me know if it is
relative to the start of the vtable or to the vtable pointer.  That'll
be enough information to do a much better job.

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer

----- End forwarded message -----

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [dmj+@andrew.cmu.edu: Re: C++ debugging progress]
  2001-11-21 15:21 ` Daniel Berlin
@ 2001-11-28 12:56   ` Daniel Berlin
  0 siblings, 0 replies; 4+ messages in thread
From: Daniel Berlin @ 2001-11-28 12:56 UTC (permalink / raw)
  To: Daniel Jacobowitz; +Cc: libstdc++, gdb

On Wed, 28 Nov 2001, Daniel Jacobowitz wrote:

> Feh.  Meant to send this to the lists.
>
> ----- Forwarded message from Daniel Jacobowitz <dmj+@andrew.cmu.edu> -----
>
> Date: Wed, 28 Nov 2001 15:18:19 -0500
> From: Daniel Jacobowitz <dmj+@andrew.cmu.edu>
> Subject: Re: C++ debugging progress
> To: Jason Merrill <jason@redhat.com>
>
> On Wed, Nov 28, 2001 at 07:40:37PM +0000, Jason Merrill wrote:
> > >>>>> "Daniel" == Daniel Jacobowitz <drow@mvista.com> writes:
> >
> > > On Wed, Nov 28, 2001 at 09:31:07AM +0000, Jason Merrill wrote:
> >
> > >> So you're using the inheritance information in the RTTI rather than the debug
> > >> info?  That seems unfortunate.  I'm not sure why you would need to worry
> > >> about ordering; the debug info should tell you exactly where things are.
> > >> If it doesn't, it should probably be fixed.
> >
> > > In that case, the debug info absolutely needs to be fixed.
> >
> > >  <1><22e>: Abbrev Number: 15 (DW_TAG_structure_type)
> > >      DW_AT_sibling     : <2df>
> > >      DW_AT_name        : Left
> > >      DW_AT_byte_size   : 12
> > >      DW_AT_decl_file   : 1
> > >      DW_AT_decl_line   : 2
> > >      DW_AT_containing_type: <22e>
> > >  <2><23f>: Abbrev Number: 22 (DW_TAG_inheritance)
> > >      DW_AT_type        : <56>
> > >      DW_AT_data_member_location: 2 byte block: 23 8 (DW_OP_plus_uconst: 8; )
> > >      DW_AT_virtuality  : 1      (virtual)
> > >      DW_AT_accessibility: 1     (public)
> >
> > Yep.  Since Base is a virtual base of Left, the DW_AT_data_member_location
> > here should be a complex expression telling the debugger to go through the
> > vtable.  I'll get on it.
>
> Thanks!
The small problem may be that we may not be able to handle it in gdb,
depending on how complex it is.
--Dan


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2001-11-28 20:56 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2001-11-28 12:18 [dmj+@andrew.cmu.edu: Re: C++ debugging progress] Daniel Jacobowitz
2001-11-21 13:26 ` Daniel Jacobowitz
2001-11-21 15:21 ` Daniel Berlin
2001-11-28 12:56   ` Daniel Berlin

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