Re: [RFA/PATCH] breakpoint.c: fix until command

Elena Zannoni
2003-01-03T23:53:41Z

Michael Snyder writes:
> Elena Zannoni wrote:
> >
> > Michael Snyder writes:
>
> > > If you say "until <line>", and the line is inside the current function,
> > > you can impose the frame restriction. If the line (or address) is outside
> > > the current function, or if you give a function name or something else,
> > > you can't. And I don't think we can code that distinction at runtime.
> >
> > I think we should come up with a behavior matrix, something like:
> >
> > until:
> > continue until next source line is reached. If already at the last line
> > of current function, continue until current frame pops.
> >
> > until line:
> > a. line in current function (1) --> continue until the line is reached.
>
> Agreed, with the qualification given.
>
> > b. line in function in inner frame --> continue until the line is reached.
>
> Agreed.
>
> > c. line in function not in inner frame --> continue until current frame pops.
>
> Agreed.
>
> > (1) However if current function is recursive, a. should become like
> > b. But we want to enforce a different behavior, because we don't
> > want to stop in the inner frame.
>
> I think this could be stated simply as "continue until the line
> is reached by the current execution frame".
>
> > --> this is the main problem,
> > because the condition is basically impossible to figure out at run
> > time.
>
> If we can figure it out at runtime, you would agree to it?
>
> > until funcname:
> > d. funcname called from current frame (2) --> continue until func is reached
>
> Agreed.
>
> > e. funcname not called from current frame --> cont until current frame pops.
>
> Agreed.
>
> > (2) if current function is recursive and funcame == current function
> > we want to stop at the next inner invocation of funcname
>
> Ow, not obvious. But since it clearly isn't specified now,
> I suppose we could make up such a stipulation if we choose to.
> I don't even know what the traditional behavior would be in
> this case.
>
>
> > The 'continue until current frame pops' behavior is already there. It
> > always puts another bp_until at the caller.
>
> Yep.
>
> So AFAICT, we have only one corner case to agree upon.
> "until factorial".

yes yes yes!

(see my previous message).