Add option to install benchmark (#463)

CMakeLists.txt

@@ -15,7 +15,8 @@ option(BENCHMARK_ENABLE_TESTING "Enable testing of the benchmark library." ON)
 option(BENCHMARK_ENABLE_EXCEPTIONS "Enable the use of exceptions in the benchmark library." ON)
 option(BENCHMARK_ENABLE_LTO "Enable link time optimisation of the benchmark library." OFF)
 option(BENCHMARK_USE_LIBCXX "Build and test using libc++ as the standard library." OFF)
-option(BENCHMARK_BUILD_32_BITS "Build a 32 bit version of the library" OFF)
+option(BENCHMARK_BUILD_32_BITS "Build a 32 bit version of the library." OFF)
+option(BENCHMARK_ENABLE_INSTALL "Enable installation of benchmark. (Projects embedding benchmark may want to turn this OFF.)" ON)
 
 # Make sure we can import out CMake functions
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")

src/CMakeLists.txt

@@ -54,8 +54,9 @@ write_basic_package_version_file(
 
 configure_file("${PROJECT_SOURCE_DIR}/cmake/Config.cmake.in" "${project_config}" @ONLY)
 
-# Install target (will install the library to specified CMAKE_INSTALL_PREFIX variable)
-install(
+if (BENCHMARK_ENABLE_INSTALL)
+  # Install target (will install the library to specified CMAKE_INSTALL_PREFIX variable)
+  install(
     TARGETS benchmark
     EXPORT ${targets_export_name}
     ARCHIVE DESTINATION ${lib_install_dir}
@@ -63,16 +64,17 @@ install(
     RUNTIME DESTINATION ${bin_install_dir}
     INCLUDES DESTINATION ${include_install_dir})
   
-install(
+  install(
     DIRECTORY "${PROJECT_SOURCE_DIR}/include/benchmark"
     DESTINATION ${include_install_dir}
     FILES_MATCHING PATTERN "*.*h")
   
-install(
+  install(
       FILES "${project_config}" "${version_config}"
       DESTINATION "${config_install_dir}")
   
-install(
+  install(
       EXPORT "${targets_export_name}"
       NAMESPACE "${namespace}"
       DESTINATION "${config_install_dir}")
+endif()