Re: Linemap and pph

[Tom Tromey <tromey at redhat dot com>]

Gabriel> We are tying to keep pph as "pluginable" as possible (Diego correct me
Gabriel> if I'm wrong), so changing the actual implementation of the linemap
Gabriel> would be our very last resort I think.

Gabriel> However since source_location aren't pointers per se, this wouldn't
Gabriel> work (at least with our current cache implementation, and changing
Gabriel> that is also last resort in my opinion)

I think something's got to give :)

Tom> Can you not just serialize the line map when creating the PPH?

Gabriel> We were wondering about that, the problem we thought is that a pph can
Gabriel> be loaded from anywhere in many different C files (which would
Gabriel> generate a different linemap entry in each case I think?). If there
Gabriel> was a way to serialize the linemap entries from the LC_ENTER entry for
Gabriel> the header file to the LC_LEAVE (i.e. ignoring builtins, command line,
Gabriel> etc.), and then directly insert those entries in a given C file
Gabriel> compilation's linemaps entries, that would be great!

Sure, I think you could probably serialize just some subset of the
linemap.  It is hard to be positive, as nobody has ever tried it, and I
don't know enough about your needs to suggest what subsetting might make
sense.

The question then is whether you are certain that the other objects you
write out are guaranteed not to reference locations outside this set.

Tom