[PATCH 3/2 xserver] travis: Enable ccache.

[Aaron Plattner]

On 06/01/2017 01:59 PM, Eric Anholt wrote:
> We bind-mount the cache directory into the container.  Cuts build time
> from about 4 minutes to 2.
> 
> Signed-off-by: Eric Anholt <eric at anholt.net>
> ---
>   .travis.yml | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/.travis.yml b/.travis.yml
> index e10cfe1e134f..0a136b23dd80 100644
> --- a/.travis.yml
> +++ b/.travis.yml
> @@ -1,4 +1,5 @@
>   language: c
> +cache: ccache
>   dist: trusty
>   services: docker
>   
> @@ -6,9 +7,9 @@ before_install:
>     - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker pull anholt/xserver-travis ; fi
>   
>   before_script:
> -  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then echo FROM anholt/xserver-travis:v3 > Dockerfile ; fi
> +  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then echo FROM anholt/xserver-travis:v4 > Dockerfile ; fi
>     - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then echo ADD . /root >> Dockerfile ; fi
>     - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker build -t withgit . ; fi
>   
>   script:
> -  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker run withgit /bin/sh -c "cd /root && ./test/scripts/travis-test.sh" ; fi
> +  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then docker run --volume $HOME/.ccache:/root/.ccache withgit /bin/sh -c "cd /root && ./test/scripts/travis-test.sh" ; fi

This doesn't apply cleanly because the previous patch names it 
build-travis-deps.sh rather than travis-test.sh. But with that fixed, 
and running the commands manually, this series seems to work.

With ccache, this took a whopping 17s on my medium-speed non-SSD 
workstation.

>