Travis: refactor matrix

.travis.yml

@@ -1,35 +1,19 @@
 language: c
 
-matrix:
+include: &toolchain_linux_amd64
-  include:
-    - env:
-      - BUILD_TYPE: shared-linux-amd64
   os: linux
   dist: trusty
   addons:
     apt:
-          packages: &linux_x64_packages
+      packages:
         - libgtk-3-dev
 
-    - env:
+include: &toolchain_linux_386
-      - BUILD_TYPE: static-linux-amd64
-      - CMAKE_FLAGS: -DBUILD_SHARED_LIBS=OFF
   os: linux
   dist: trusty
   addons:
     apt:
-          packages: *linux_x64_packages
+      packages:
-
-    - env:
-      - BUILD_TYPE: shared-linux-386
-      - CFLAGS: -m32
-      - CXXFLAGS: -m32
-      - PKG_CONFIG_PATH: /usr/lib/i386-linux-gnu/pkgconfig
-      os: linux
-      dist: trusty
-      addons:
-        apt:
-          packages: &linux_i386_packages
         - gcc-multilib
         - g++-multilib
         - libgtk-3-dev:i386
@@ -47,29 +31,36 @@ matrix:
         - libxft-dev:i386
         - libpng12-dev:i386
 
-    - env:
+include: &toolchain_osx_amd64
-      - BUILD_TYPE: static-linux-386
-      - CMAKE_FLAGS: -DBUILD_SHARED_LIBS=OFF
-      - CFLAGS: -m32
-      - CXXFLAGS: -m32
-      - PKG_CONFIG_PATH: /usr/lib/i386-linux-gnu/pkgconfig
-      os: linux
-      dist: trusty
-      addons:
-        apt:
-          packages: *linux_i386_packages
-
-    - env:
-      - BUILD_TYPE: shared-osx-amd64
   os: osx
   osx_image: xcode8
 
-    - env:
+# Travis CI build matrix.
-      - BUILD_TYPE: static-osx-amd64
+# Each entry below will trigger an extra, parallel build on Travis.
-      - CMAKE_FLAGS: -DBUILD_SHARED_LIBS=OFF
+matrix:
-      os: osx
+  include:
-      osx_image: xcode8
+    - env: linking=shared platform=amd64
+      <<: *toolchain_linux_amd64
+    - env: linking=static platform=amd64
+      <<: *toolchain_linux_amd64
+    - env: linking=shared platform=386
+      <<: *toolchain_linux_386
+    - env: linking=static platform=386
+      <<: *toolchain_linux_386
+    - env: linking=shared platform=amd64
+      <<: *toolchain_osx_amd64
+    - env: linking=static platform=amd64
+      <<: *toolchain_osx_amd64
 
+install:
+  - if [[ "${platform}" == "386" ]]; then
+      export CFLAGS=-m32;
+      export CXXFLAGS=-m32;
+      export PKG_CONFIG_PATH=/usr/lib/i386-linux-gnu/pkgconfig;
+    fi
+  - if [[ "${linking}" == "static" ]]; then
+      export CMAKE_FLAGS=-DBUILD_SHARED_LIBS=OFF;
+    fi
 
 script:
   - cmake --version