Add test for 32-bit target. (#209)

.travis.yml

@@ -56,6 +56,9 @@ matrix:
     - env: BUILD_TARGET="posix"
       compiler: gcc
       os: osx
+    - env: BUILD_TARGET="posix-32-bit"
+      compiler: gcc
+      os: linux
     - env: BUILD_TARGET="cc2538"
       compiler: gcc
       os: linux

.travis/before_install.sh

@@ -50,6 +50,10 @@ cd /tmp || die
     [ $BUILD_TARGET != scan-build ] || {
         sudo apt-get install clang || die
     }
+
+    [ $BUILD_TARGET != posix-32-bit ] || {
+        sudo apt-get install g++-multilib || die
+    }
 }
 
 [ $TRAVIS_OS_NAME != osx ] || {

.travis/script.sh

@@ -46,6 +46,10 @@ set -x
     make -f Makefile-Standalone distcheck || die
 }
 
+[ $BUILD_TARGET != posix-32-bit ] || {
+    CFLAGS=-m32 CXXFLAGS=-m32 LDFLAGS=-m32 make -f Makefile-Standalone distcheck || die
+}
+
 [ $BUILD_TARGET != cc2538 ] || {
     export PATH=/tmp/gcc-arm-none-eabi-4_9-2015q3/bin:$PATH || die
     make -f examples/cc2538/Makefile-cc2538 || die