CMakeLists: Make boost an interface library target

Gets rid of the use of a non-target include and makes libraries
explicitly link against the identifier name in order to get includes.

.appveyor.yml

@@ -18,7 +18,7 @@ install:
 before_build:
   - mkdir build
   - cd build
-  - cmake .. -G "Visual Studio 14 2015 Win64" -DDYNARMIC_USE_SYSTEM_BOOST=0 -DBoost_INCLUDE_DIRS=externals/boost
+  - cmake .. -G "Visual Studio 14 2015 Win64" -DDYNARMIC_USE_SYSTEM_BOOST=0 -DBoost_INCLUDE_DIRS=%cd%/../externals/boost
   - cd ..
 
 build:

.travis/build.sh

@@ -11,7 +11,7 @@ if [ "$TRAVIS_OS_NAME" = "linux" -o -z "$TRAVIS_OS_NAME" ]; then
     export PKG_CONFIG_PATH=$HOME/.local/lib/pkgconfig:$PKG_CONFIG_PATH
 
     mkdir build && cd build
-    cmake .. -DDYNARMIC_USE_SYSTEM_BOOST=0 -DBoost_INCLUDE_DIRS=externals/ext-boost
+    cmake .. -DDYNARMIC_USE_SYSTEM_BOOST=0 -DBoost_INCLUDE_DIRS=${PWD}/../externals/ext-boost
     make -j4
 
     ctest -VV -C Release
@@ -21,6 +21,6 @@ elif [ "$TRAVIS_OS_NAME" = "osx" ]; then
     export MACOSX_DEPLOYMENT_TARGET=10.9
 
     mkdir build && cd build
-    cmake .. -GXcode -DDYNARMIC_USE_SYSTEM_BOOST=0 -DBoost_INCLUDE_DIRS=externals/ext-boost -DDYNARMIC_TESTS=0
+    cmake .. -GXcode -DDYNARMIC_USE_SYSTEM_BOOST=0 -DBoost_INCLUDE_DIRS=${PWD}/../externals/ext-boost -DDYNARMIC_TESTS=0
     xcodebuild -configuration Release
 fi

CMakeLists.txt

@@ -109,7 +109,8 @@ else()
         message(FATAL_ERROR "Please provide a path to a boost installation using Boost_INCLUDE_DIRS")
     endif()
 endif()
-include_directories(${Boost_INCLUDE_DIRS})
+add_library(boost INTERFACE IMPORTED)
+set_property(TARGET boost PROPERTY INTERFACE_INCLUDE_DIRECTORIES ${Boost_INCLUDE_DIRS})
 
 # Enable unit-testing.
 enable_testing(true)

src/CMakeLists.txt

@@ -111,9 +111,7 @@ target_include_directories(dynarmic
                            PRIVATE .)
 target_compile_options(dynarmic PRIVATE ${DYNARMIC_CXX_FLAGS})
 
-# Link fmt
-target_link_libraries(dynarmic PRIVATE fmt-header-only)
+target_link_libraries(dynarmic PRIVATE boost fmt-header-only xbyak)
 if (CMAKE_SYSTEM_NAME STREQUAL "Windows")
     target_compile_definitions(dynarmic PRIVATE FMT_USE_WINDOWS_H=0)
 endif()
-target_link_libraries(dynarmic PRIVATE xbyak)

tests/CMakeLists.txt

@@ -35,7 +35,7 @@ include(CreateDirectoryGroups)
 create_directory_groups(${SRCS} ${HEADERS})
 
 add_executable(dynarmic_tests ${SRCS})
-target_link_libraries(dynarmic_tests dynarmic catch ${llvm_libs})
+target_link_libraries(dynarmic_tests PRIVATE dynarmic boost catch ${llvm_libs})
 set_target_properties(dynarmic_tests PROPERTIES LINKER_LANGUAGE CXX)
 target_include_directories(dynarmic_tests PRIVATE . ../src)
 target_compile_options(dynarmic_tests PRIVATE ${DYNARMIC_CXX_FLAGS})