Re: c++/2208: Checkpoints not saved on restart

Re: c++/2208: Checkpoints not saved on restart

[Uri Moszkowicz]

Hi,
I submitted this bug report and am forwarding it to this list at the
request of Nick Roberts. This bug concerns checkpointing and is
probably more of a feature request than a bug (though I've submitted
several other real checkpointing bugs).

While I'm glad to have checkpointing support, its not as useful as it
may appear since you can only revert to a saved checkpoint once. After
restarting a saved checkpoint it is lost. I propose that a restart
checkpoint should first fork before execution thus allowing a user to
replay from a given checkpoint multiple times.

Checkpointing after any restart would be a temporary workaround except
for bug #2209, which states that checkpointing after restart causes a
deadlock.

Thanks,
Uri

On 1/3/07, Nick Roberts <nickrob@snap.net.nz> wrote:
> http://sourceware.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gdb&pr=2208
>
> > 1. set 2 breakpoint and run to first
> > 2. "checkpoint"
> > 3. "continue"
> > 4. "restart 1"
> > 5. "continue"
> > 6. "info checkpoints"
>
> > Notice how checkpoint 1 has moved to the second breakpoint.
>
> I think that's because 5. "continue" took it there.  Have you read the
> description of checkpoints in the manual?  I think it's a good idea
> to post to gdb@sources.redhat.com first, and only file as a bug once
> there is agreement that it is one.
>
>

Re: c++/2208: Checkpoints not saved on restart

[Nick Roberts]

 > While I'm glad to have checkpointing support, its not as useful as it
 > may appear since you can only revert to a saved checkpoint once. After
 > restarting a saved checkpoint it is lost.

Presumably when you restart you can create another checkpoint if you wish
to go back there again.

-- 
Nick                                           http://www.inet.net.nz/~nickrob

Re: c++/2208: Checkpoints not saved on restart

[Uri Moszkowicz]

Assuming bug #2209 were fixed, yes you could. It would be nice if that
were at least an option though, if not the default. I think of them as
similar to breakpoints. Perhaps GDB should distinguish between
temporary checkpoints and regular checkpoints, with the latter being
permanent of course.

On 1/10/07, Nick Roberts <nickrob@snap.net.nz> wrote:
>  > While I'm glad to have checkpointing support, its not as useful as it
>  > may appear since you can only revert to a saved checkpoint once. After
>  > restarting a saved checkpoint it is lost.
>
> Presumably when you restart you can create another checkpoint if you wish
> to go back there again.
>
> --
> Nick                                           http://www.inet.net.nz/~nickrob
>