Thanks @gthess. Sorry I could not run the tests before it landed on your desk.

OK, the first Travis results are good. Most platforms tested OK. The one failure is OS X.

You have several choices now. First, you can add OS X as an allowed failure so Travis will report success. So you can add this to the bottom of .travis.yml:

  allow_failures:
    -os: osx

OS X provides an antique version OpenSSL, so you will probably want to update it eventually so the test succeeds.

Second, you can use Brew to install an updated version of OpenSSL. That might looks something like this:

before_install:
  - |
    if [ "$TRAVIS_OS_NAME" = "osx" ]; then
        brew update
        brew install openssl
    fi

Third, you can fetch OpenSSL using curl, and build and install OpenSSL in the before_install recipe. The one sharp edge is, OS X provides curl out of the box, not wget.

The choice is Unbound's how to proceed.

Nice, thanks for this!
We were also thinking about the brew option. If the osx test passes this PR is ready.

Thanks @gthess.

I think we are close. Here is the failed configure message after the Brew install of OpenSSL.

checking for SSL... configure: error: Cannot find the SSL libraries in /usr/local/ssl /usr/lib/ssl /usr/ssl /usr/pkg /usr/local /opt/local /usr/sfw /usr

I'm thinking configure may need to look in /usr/local for Brew installs of OpenSSL on OS X. That is, headers are in /usr/local/include and libs are in /usr/local/lib. But it is just a guess at this point.

I asked a question on the Travis message boards at Where does Brew install OpenSSL on OS X?

I did some tests and it seems that
/configure --enable-debug --disable-flto --with-ssl=/usr/local/opt/openssl/
works; merged it.
Thanks again!

@gthess,

Here's some reading on Travis and C projects. Another good page is Build Environments, where you can find what is available for Linux, OS X, Windows, etc. You can also find the environmental variables like TRAVIS_OS_NAME.

Generally speaking, use Bionic images unless you are testing an old compiler. Old compilers give trouble using Trusty and Xenial on PowerPC and s390x. Testing old compilers (like GCC 4.8) is fine, you just have to know what to expect.

Also, avoid the "matrix expansion". You do that by (1) avoiding the top level keys like os: and compiler:, and (2) specifying the exact job you want to run in jobs:.

For example, don't do this (this implicitly creates the matrix expansion):

# top level keys
os:
  - linux
  - osx
compiler:
  - gcc
  - clang

Instead, do this (this is what you are doing now):

# only job is top level
jobs:
  include:
    - os: linux
      compiler: gcc
      arch: amd64
      dist: bionic
    - os: linux
      compiler: clang
      arch: amd64
      dist: bionic
    ...

Avoiding matrix expansion will save you a lot of headaches down the road when you are trying to craft tests on platforms. Especially if you add Android and iOS testing.