[yocto] Errors building with Windows Subsystem for Linux (aka Bash on Ubuntu on Windows)

[Mark Hatle]

On 9/28/17 8:28 AM, Bryan Evenson wrote:
> Ross,
> 
>  
> 
> *From:*Burton, Ross [mailto:ross.burton at intel.com]
> *Sent:* Wednesday, September 27, 2017 6:43 PM
> *To:* Bryan Evenson <bevenson at melinkcorp.com>
> *Cc:* yocto at yoctoproject.org
> *Subject:* Re: [yocto] Errors building with Windows Subsystem for Linux (aka
> Bash on Ubuntu on Windows)
> 
>  
> 
> On 27 September 2017 at 21:59, Bryan Evenson <bevenson at melinkcorp.com
> <mailto:bevenson at melinkcorp.com>> wrote:
> 
>      
> 
>     I think I found the problem.  I started looking at more file properties for
>     the files that worked and the ones that didn’t, and I noticed that all the
>     ones that failed show a link count of 1024.  The Windows filesystem has a
>     link limit of 1023 links per file (at least as reported here:
>     https://msdn.microsoft.com/en-us/library/windows/desktop/aa363860(v=vs.85).aspx),
>     so I think the hard link is failing due to the Windows link limit.  If that
>     is the case, then I don’t think it’ll be a quick fix to get a working
>     solution under WSL.
> 
>  
> 
> That link count doesn't seem feasible though...  we hardlink frequently during a
> recipe build, but I'd expect to see 10 links, not over a thousand.  You've
> definitely found the problem, just need to figure out what is causing such
> excessive linking,
> 
>  
> 
> Two files, LC_MEASUREMENT and LC_PAPER, seem to be identical through most the
> locales.  I’m not sure which are copies and which are hard links, but I did a
> md5sum comparison and found over 1200 identical LC_MEASUREMENT files in the
> glibc-locale working directory.  I don’t need all the locales, so I set
> GLIBC_GENERATE_LOCALES = "en_GB.UTF-8 en_US.UTF-8" in my local.conf and now
> glibc-locale completes building.
> 

FYI, this is expected.  The locales have numerous copies of the same files for
the same locales.  So to save space there is a step that runs and identifies the
duplicates and hard links them.  (This helps a lot for the sstate-cache for
instance).

It likely wouldn't be difficult to determine the link count 'issue' and simply
link to a different file for subsequent links... but I'm no longer sure where
the linking occurs that does all of this.

--Mark

> 
> I’ll report back if the rest of the build completes.
> 
>  
> 
> Bryan
> 
>  
> 
> 
>