[ccache] Testing on other platforms (than Linux)

[Anders Björklund]

Hi ccache!

We have earlier had some problems on testing on other *Unix* platforms,
like Solaris or FreeBSD. Mostly because none of us are running those...

https://github.com/ccache/ccache/issues/148

https://svnweb.freebsd.org/ports/head/devel/ccache/

We are also seeing some bugs that are "unique" to either Mac or Win,
but hard to reproduce with regular Clang or MinGW running on Linux.

https://github.com/ccache/ccache/issues/54
https://github.com/ccache/ccache/issues/156

https://github.com/ccache/ccache/issues/95
https://github.com/ccache/ccache/issues/122


Lately we had some discussion on this, with Joel explaining his view:
https://github.com/ccache/ccache/pull/162#issuecomment-289215585

We could need some more ideas, on how to make this work better ?
Meanwhile, I've updated Clang and MinGW so that they work again.

I also added a Docker build to define the "basic platform" and
plan on extending this with clang and mingw (like in Travis)

Also updated some more of the "clang-analyzer" tests, and to the
new 64-bit versions of MinGW-w64 and Wine64 (instead of 32-bit).


But what would be the best option to keep the base project both
clean and portable ? And how to make it easier to test/contribute.

I think the current infrastructure with Travis, and now Docker, are
a good baseline, maybe we could add some Mac or Win in the cloud ?

I know that we have access to Appveyor (we tried to use it before),
and that the new "MSYS2" is looking promising (although is very slow)

https://github.com/ccache/ccache/pull/69
http://www.msys2.org/ (uses Pacman, yeah!)


But are there any better options, or more people wanting to help out ?

My plan was to try to get the memcached and compression working instead.

https://github.com/ccache/ccache/pull/58
(+ https://github.com/ccache/ccache/pull/104)

https://github.com/ccache/ccache/pull/118
(+ https://github.com/ccache/ccache/pull/81)

/Anders