In practice, we hardly ever get different outcomes, so there is no
gain in running tests with different compilers.
Experimentally, with the builds and tests we currently do and with the
compiler versions on a Travis Ubuntu 16.04, gcc jobs are significantly
faster than clang jobs (13 min vs 24 min). So use gcc.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
This is what we do in Jenkins, so it only makes sense to do it here as well.
This will avoid random failures for no other reason than the proxy was
dropping all the messages due to an unlucky PRNG seed.
See https://docs.travis-ci.com/user/environment-variables/ for syntax
Apparently the version of openssl available on travis machines does not
support all the ciphersuites expected by compat.sh. While waiting for this
script to handle various openssl versions better, just disable openssl.
Causing spurious fails of ssl-opt.sh. Likely a version issue. It would be
better to investigate the exact problem, and maybe adapt ssl-opt.sh to be
check for a minimum version just as compat.sh does, but this is a quick fix.