Re: [PATCH] -stack-info-frame/-stack-list-frames

Nick Roberts
2008-04-23T23:23:52Z

> You gave a perfect example in your other reply, just now, of why front
> ends should not have a frame address. If you are ever in the position
> of dealing with a recursive function and you want to know which
> instance a variable comes from, the frame address is insufficient.
> For instance IA-64 can have stackless recursive functions; they
> use only the separate register stack.

Well you understand the internals much better than I do, but whenever I've
looked at the frame addresses on i386 they've appeared meaningful. Are
"stackless recursive functions" special to IA-64 or a consequence of
optimisation? If the values are meaningful "most of the time" then I think
it's OK to have this field, if not then I guess it might just confuse.

> If you want to know which frame the varobj is associated with GDB
> should supply some unique opaque identifier, and then the IDE can
> use that to show the frame number in a tooltip or wherever.

Do you mean use something like uuidgen to associate a key with a frame
and output that as a field for a variable object?