[Gnu-arch-users] progress on building backwards

[Aaron Bentley]

Hi all,

The way I work, it can be a pain when you need an older revision that
isn't in your library.  tla will go back to the newest version it can
find, but sometimes that's *very* old.  

If you knew in advance, you could produce the revision by hand by
getting a newer version, and reverse-replaying a few revisions.

So I've been working on getting build-revision to be bi-directional--
that is, to be able to build an old revision from a newer one, where
appropriate.

The first successful back-build happened last night.  Also, performance
has been improved by snapping inodes only once the target revision has
been built.  (In one test, this improved build speed 2.35 x)

Getting this far has involved heavy refactoring.  build_revision.c used
to contain 1 monolithic recursive function, and now it's 14
non-recursive functions.

Currently, the code is functional, but messy.  (has memory leaks, style
problems, ignores all other import sources when library revisions are
present)

If you're curious (and have a strong stomach), you can see it here:
address@hidden/tlasrc--backbuild--0--patch-14
http://sourcecontrol.net/~abentley/archives/tlasrc/
I am not aware of any bugs, but take care.  I hope to have something
more presentable in the next few days.  

In the meantime, can I ask you to hold off on changing
build-revision.c?  Changes are pretty much guaranteed to conflict with
my code, and they may not even be relevent to the back-builder version.

I know Tom wants to get 1.2final out soon, and I hope he can, so that
back-building can go into 1.3.

Aaron

-- 
Aaron Bentley
Director of Technology
PanoMetrics, Inc.