Index: test-suite/trunk/MicroBenchmarks/XRay/CMakeLists.txt
===================================================================
--- test-suite/trunk/MicroBenchmarks/XRay/CMakeLists.txt
+++ test-suite/trunk/MicroBenchmarks/XRay/CMakeLists.txt
@@ -1,2 +1,8 @@
 add_subdirectory(ReturnReference)
-add_subdirectory(FDRMode)
+if(NOT TARGET_OS STREQUAL "Darwin")
+  # FDRMode test is failing on Darwin because
+  # `__xray_log_select_mode("xray-fdr")` returns `XRAY_MODE_NOT_FOUND`.
+  #
+  # Disable the test until it is fixed. rdar://problem/44578416
+  add_subdirectory(FDRMode)
+endif()