[Buildbot-devel] Running Shell Commands

[Brian Warner]

I played around a bit with this.. it seems that there are a couple of ways to
mess up the argv array that result in 'make' trying to build something that's
not going to work, which then causes .config to be corrupted. Once .config is
mussed, those same commands fail with an error from Make, because they're
including .config (which is no longer a valid Makefile).

In particular, if the top-level Makefile doesn't recognize the target you're
building as one that creates a config file, it will attempt to 'include
.config', which will fail if .config is corrupted. So my hunch is that you
got a corrupted .config while you were getting to the correct argv value, and
that builds still using the wrong argv value would cause the Make error you
described. Something like ['make', 'allmodconfig > .config'] is one such
troublesome argv value, as it attempts to build a target named 'allmodconfig
> .config', which doesn't exist, while ['make', '-d', 'allmodconfig >
.config'] (which I did while trying to figure out what target 'allmodconfig >
.config' made it build) produced a corrupted .config file, even though the
top-level shell was not being asked to redirect anything to .config. I
suspect that somewhere the Makefile is spawning off a sub-Make, and passing
its target to that invocation with a regular '/bin/sh -c', so the shell
redirection is happening when that internal Make runs.

Try deleting .config altogether, then re-running the step. Actually, the way
to do this is to write a shell script that starts with nothing, does the
checkout, then does all the desired commands. Don't try to write the build
steps until that script works without human intervention. One of the problems
with complex persistent-configuration systems like the linux kernel is that
it's hard to know what state is "sticky", and a human-edited tree may have
something lying around that makes it all work, which the completely
machine-generated one might not have.

let me know how that goes,
 -Brian