[Buildroot] full rebuild and errors

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Dear Arnout Vandecappelle,

On Wed, 29 Jan 2014 08:14:09 +0100, Arnout Vandecappelle wrote:

> > No, it doesn't. The cache of ccache is located in
> > ~/.buildroot-ccache/, because the intent of ccache is precisely to be
> > able to re-use the cache contents across complete rebuilds, and even
> > across multiple clones of Buildroot.
> 
>   But this is yet another proof that it doesn't work very well. And this 
> one really worries me, because it's a host build that failed.

And for what it worth just two days ago, one of my colleague also had a
weird compilation problem while building host-gettext (the link step
was complaining because one of the object file it was given was built
for i386, while the host machine is x86-64, and therefore the link was
failing). The problem was reproducible even after a complete 'make
clean all' cycle. And it turned out that clearing the cache solved the
problem, so it was indeed a mis re-use of an existing object file.

And it was also on the build of a host package, which is really weird.
We know that our ccache handling is far from perfect in terms of
detecting a change of the target compiler, but I wasn't aware of any
theoretical problem regarding the build of host packages.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com