Merge pull request #15 from mapbox/clang38

Install clang via mason

.travis.yml

@@ -10,13 +10,23 @@ matrix:
           sources: [ 'ubuntu-toolchain-r-test' ]
           packages: [ 'g++-5' ]
     - os: linux
-      env: CXX=clang++-3.7
+      env: CXX=clang++-3.8
       addons:
         apt:
-          sources: [ 'ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.7' ]
-          packages: [ 'clang-3.7' ]
+          sources: [ 'ubuntu-toolchain-r-test' ]
+          packages: [ libstdc++-5-dev', 'libstdc++6', 'g++-5' ]
 
 cache: apt
 
+install:
+  - |
+    if [[ ${CXX} =~ "clang" ]] && [[ $(uname -s) == "Linux" ]]; then
+      ./.mason/mason install clang 3.8.0
+      CLANG_PREFIX=$(./.mason/mason prefix clang 3.8.0)
+      export PATH=${CLANG_PREFIX}/bin:${PATH}
+      which clang++
+      clang++ -v
+    fi
+
 script:
  - make test

Makefile

@@ -10,15 +10,15 @@ RAPIDJSON_DEP = `$(MASON) cflags $(RAPIDJSON)`
 
 default: build/libgeojson.a
 
-mason_packages:
+mason_packages/headers/geometry:
 	$(MASON) install $(VARIANT)
 	$(MASON) install $(GEOMETRY)
 	$(MASON) install $(RAPIDJSON)
 
 build:
 	mkdir -p build
 
-build/geojson.o: src/mapbox/geojson.cpp include/mapbox/geojson.hpp build mason_packages Makefile
+build/geojson.o: src/mapbox/geojson.cpp include/mapbox/geojson.hpp build mason_packages/headers/geometry Makefile
 	$(CXX) $(CFLAGS) $(CXXFLAGS) $(DEPS) $(RAPIDJSON_DEP) -c $< -o $@
 
 build/libgeojson.a: build/geojson.o