[PATCH REPOST 2/7] kbuild: fixdep: support concatenated dep files

[Stephen Warren]

On 03/21/2013 12:23 PM, Stephen Warren wrote:
> From: Stephen Warren <swarren at nvidia.com>
> 
> The current use-case for fixdep is: a source file is run through a single
> processing step, which creates a single dependency file as a side-effect,
> which fixdep transforms into the file used by the kernel build process.
> 
> In order to transparently run the C pre-processor on device-tree files,
> we wish to run both gcc -E and dtc on a source file in a single rule.
> This generates two dependency files, which must be transformed together
> into the file used by the kernel build process. This change modifies
> fixdep so it can process the concatenation of multiple separate input
> dependency files, and produce a correct unified output.
> 
> The code changes have the slight benefit of transforming the loop in
> parse_dep_file() into more of a lexer/tokenizer, with the loop body being
> more of a parser. Previously, some of this logic was mixed together
> before the loop. I also added some comments, which I hope are useful.
> 
> Benchmarking shows that on a cross-compiled ARM tegra_defconfig build,
> there is less than 0.5 seconds speed decrease with this change, on top
> of a build time of ~2m24s. This is probably within the noise.

Marek, do patches 2, 3, and 4 in this series look good to you from a
kbuild perspective?

I'm hoping that you can review/ack those 3 patches for kbuild, and that
Grant will review/ack the whole series, and then the series can be
merged via arm-soc for 3.10.

Let me know if you need me to repost the series again in case it's
fallen out of your inbox.

Thanks.