Add a CMake option controlling whether to link to libatomic. Refs #169.

CMakeLists.txt

@@ -22,12 +22,34 @@ target_link_libraries(boost_uuid
 
 target_compile_features(boost_uuid INTERFACE cxx_std_11)
 
-if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND NOT CMAKE_CXX_COMPILER_FRONTEND_VARIANT STREQUAL "MSVC"))
+# Link Boost::uuid to libatomic
+
+set(_def_linkatomic OFF)
+
+if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+
+  set(_def_linkatomic ON)
+
+endif()
+
+if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND NOT CMAKE_CXX_COMPILER_FRONTEND_VARIANT STREQUAL "MSVC")
+
+  set(_def_linkatomic ON)
+
+endif()
+
+option(BOOST_UUID_LINK_LIBATOMIC "Boost.UUID: link Boost::uuid to libatomic" ${_def_linkatomic})
+
+unset(_def_linkatomic)
+
+if(BOOST_UUID_LINK_LIBATOMIC)
 
   target_link_libraries(boost_uuid INTERFACE atomic)
 
 endif()
 
+# Testing support
+
 if(BUILD_TESTING AND EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/test/CMakeLists.txt")
 
   add_subdirectory(test)