cmake: do not link against librt on osx

as osx does not offer librt

Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 6401e2d66aae9dafab1e9ee1fd7ec5a618042c4b..b218a0eeaea05b83971ec59e7c4014199d05ccab 100644 (file)
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -170,7 +170,10 @@ if(COMPILER_SUPPORTS_DIAGNOSTICS_COLOR)
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fdiagnostics-color=${DIAGNOSTICS_COLOR}")
 endif()
 
-set(EXTRALIBS rt ${CMAKE_DL_LIBS} ${ATOMIC_OPS_LIBRARIES})
+set(EXTRALIBS ${CMAKE_DL_LIBS} ${ATOMIC_OPS_LIBRARIES})
+if(NOT APPLE)
+  list(APPEND EXTRALIBS rt)
+endif()
 if(LINUX)
   set(LIB_RESOLV resolv)
   list(APPEND EXTRALIBS ${LIB_RESOLV})