Another attempt at building cmake from source

.travis.yml

@@ -132,13 +132,16 @@ before_install:
       brew install -y https://raw.githubusercontent.com/Homebrew/homebrew-core/5b680fb58fedfb00cd07a7f69f5a621bb9240f3b/Formula/doxygen.rb;
       sudo pip install -U pytest --ignore-installed six;
     fi
+  # The cmake version installed by apt on ARM and PPC is very old,
+  # so build a more recent version from source.
   - if [[ "${TRAVIS_CPU_ARCH}" == "ppc64le" || "${TRAVIS_CPU_ARCH}" == "arm64" ]]; then
       wget https://github.com/Kitware/CMake/releases/download/v3.17.1/cmake-3.17.1.tar.gz;
       tar xf cmake-3.17.1.tar.gz;
       cd cmake-3.17.1;
       ./bootstrap;
-      make;
-      sudo make install;
+      make -j 4;
+      echo ${HOME};
+      export PATH=${HOME}/bin:${PATH};
     fi
   #- if [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then
   #    CMAKE_URL="http://cmake.org/files/v3.7/cmake-3.7.2-Linux-x86_64.tar.gz";