Re: [Tack-devel] Prime Mover commands

[David G. <dg...@co...>]

tim kelly wrote:
[...]
>> pm.intermediatecache =3D o
>=20
> I did some digging into the pm script in the Subversion web interface a=
nd
> found that this perhaps should be pm.intermediate_cache_dir, which seem=
s to
> give the desired results.

Oops! Sorry --- I should know better than to trust my memory late at nigh=
t...

[...]
> I really like the INDEX principle, by the way.  I do a lot of "objdump =
-d"s
> on object files, so having something that caches the builds allows me t=
o
> compare changes between flags (like -On) much easier.  It also undersco=
res
> the need for being able to change the intermediate cache directory, so =
that
> instead of all of the cached object files going into a single directory=
, a
> shadow object file tree can be constructed for easier traversal.

Unfortunately, that's not what the intermediate cache is for --- it's not=
 the
final destination of the built files, it's where pm stores (for its own
nefarious purposes) the *intermediate files* it uses to build things. It'=
s not
supposed to be public, which is why it defaults to a hidden directory. (I=
n
fact, the only reason the files in there have human-readable names is to =
make
debugging easier. The first version called everything 1.o, 2.o, 3.o, 4.a,=
 etc.)

If you want access to anything pm makes, you have to export it using 'ins=
tall
=3D pm.install()'. If you want access to all .o files, you should be able=
 to do
this by subclassing the cfile{} rule.

[long example removed --- it actually turned out to be more interesting t=
han I
expected, so I checked it in. See:

http://svn.sourceforge.net/viewvc/*checkout*/primemover/pm/test-pmfiles/c=
omplex-c-program.pm?revision=3D33

I also found a bug in c.pm, so you'll need a new version of that as well =
if
you want rebuilding to work properly.]

> How do I do a "Save and Restore" for the pm.intermediate_cache_dir sett=
ing,
> so that it is local in scope wrt to the pmfile, or even the object bein=
g
> built?

You can't, I'm afraid --- once execution of your pmfile script has finish=
ed,
whatever value you last set it as sticks. It *might* be possible to trick=
 pm
into running code where you change it, but all that's likely to happen is=

horribly confusing pm.

> This, of course,
> brings up a question I've had regarding threaded builds, equivalent to =
make
> -Jn where n is the number of threads (which also invokes stuff like .WA=
IT
> and the like).

Currently not on the drawing boards... sorry! pm guarantees the order in =
which
things are built (nodes are recursed into in strict depth-first order) wh=
ich
means threaded builds would be Really Hard. However, if you build with -p=
ipe
you should get most of the benefits of having a multiprocessor machine wi=
thout
needing them.

--=20
+- David Given --McQ-+ "Gaping from its single obling socket was
|  dg...@co...    | scintillating, many fauceted scarlet emerald..."
| (dg...@ta...) | --- Jim Theis, _The Eye of Argon_ (spelling
+- www.cowlark.com --+ original)