[OE-core] Getting "File name too long" errors in warrior for sstate-cache names

[Richard Purdie]

On Mon, 2019-11-11 at 14:49 +0000, Mike Looijmans wrote:
> Starting with warrior build, I'm getting build fails due to "File
> name too 
> long" in sstate-cache filenames. This is probably related to having
> long names 
> for machines, but this did not happen in previous releases. For
> example:
> 
> OSError: [Errno 36] File name too long: 
> '/mnt/.../sstate-cache/52/sigtask.9u_r4yv2' -> 
> '/mnt/.../sstate-cache/52/sstate:u-boot-
> xlnx:topic_miamilite_florida_test_xc7z010-oe-linux-gnueabi:v2019.01-
> xilinx-
> v2019.1+gitAUTOINC+d895ac5e94:r0:topic_miamilite_florida_test_xc7z010
> :3:52cb29cef3922da53a752f38e9bbfdef878af51813dc095d9c1451d572844f93_p
> repare_recipe_sysroot.tgz.siginfo'
> 
> 
> What can I do about this? There's no hint in the error message and
> searching 
> for the message text doesn't show much except issues with crypto
> filesystems, 
> which doesn't apply. The filesystem is just plain ext4.

There have been a few reports of this and an open bug. The trigger was
probably the switch from md5 to sha256. Unfortunately we haven't
figured out a good patch to address it yet. In your case it looks like
a long recipe name combined with git versions (also longer). Truncating
the PN and/or PV would probably help work around it, the hash is the
key piece for sstate and the rest is just to help humans.

Cheers,

Richard