[bitbake-devel] [PATCH 2/2] bitbake: implement checksums for local files in SRC_URI

[Paul Eggleton]

On Tuesday 22 May 2012 18:45:23 you wrote:
> On 5/22/12 6:23 PM, Paul Eggleton wrote:
> > Gathers a list of paths to have checksums calculated at parse time, and
> > processes these when calculating task hashes. Checksums are cached with
> > the file's current mtime. Thus, changing any local file in SRC_URI will
> > now cause the do_fetch taskhash to change, thus forcing a rebuild.
> 
> Does the mtime change invalidate the checksum, or just cause the checksum to
> be re-interpreted?

The latter.

> The issue I see is that you share a ccache file with someone else, their
> files may simply have a different mtime on them.

I'm guessing s/ccache/sstate cache/ ?

This will be fine - only the checksum of the file contents goes into the sstate 
signature.

>  From reading the code below, I think the comment is just confusing me.  The
> checksum is computed and stored bases on a hash + mtime.  If the mtime
> changes, that will cause the system to recalculate the checksum, which may
> end up being the same.. (and if it is, no rebuild) right?

Correct.

Cheers,
Paul

-- 

Paul Eggleton
Intel Open Source Technology Centre