quickly build a single program ?

[Giorgos Keramidas]

On Sun, 25 Jan 2009 08:23:41 +0100, Luigi Rizzo <rizzo at iet.unipi.it> wrote:
>On Sat, Jan 24, 2009 at 05:26:33AM +0200, Giorgos Keramidas wrote:
>>On Sat, 24 Jan 2009 00:36:11 +0100, Luigi Rizzo <rizzo at iet.unipi.it> wrote:
>>> how hard would it be to modify the build scripts so that they only try
>>> to rebuild a single program from a tree where you already made a buildworld ?
>>>
>>> i usually do modifications to a single program at a time and it is
>>> slightly annoying to wait for the build process to scan through all
>>> the already-built programs to find there is nothing to do for them.
>>
>> Most of the time, when there are small changes I just change into the
>> program's directory and `make'.   But this doesn't work when there are
>> dependencies with other parts of buildworld.
>
> ... or when you work on a different tree than the one installed,
> unless there is an easy way to set the environment variables
> to point to the correct toolchain and headers/libraries ?
>
> Maybe that's all i need in the end.

Yes, that would probably be nice.  We have `make buildenv' now,
but IIRC it does not actually *build* anything.  It only set up
environment vars to point to the correct places in /usr/obj and
spawns sh.

I think it may be useful to add a few bits in `Makefile.inc1' to
actually *build* the stages up to _depend with -DNO_CLEAN and
then spawn a shell.  That would be cool :-)