diff --git a/External/SPEC/CINT2017rate/500.perlbench_r/CMakeLists.txt b/External/SPEC/CINT2017rate/500.perlbench_r/CMakeLists.txt
--- a/External/SPEC/CINT2017rate/500.perlbench_r/CMakeLists.txt
+++ b/External/SPEC/CINT2017rate/500.perlbench_r/CMakeLists.txt
@@ -6,6 +6,10 @@
 
 speccpu2017_benchmark(RATE)
 
+if (TARGET_OS STREQUAL "Darwin")
+  add_definitions(-DSPEC_MACOSX_X64)
+endif ()
+
 add_definitions(
   -DPERL_CORE
   -DDOUBLE_SLASHES_SPECIAL=0
diff --git a/External/SPEC/SpecCPU2017.cmake b/External/SPEC/SpecCPU2017.cmake
--- a/External/SPEC/SpecCPU2017.cmake
+++ b/External/SPEC/SpecCPU2017.cmake
@@ -158,6 +158,8 @@
       list(APPEND SPEC_COMMON_DEFS "-DSPEC_LINUX_AARCH64")
     elseif (ARCH STREQUAL "x86" AND TARGET_OS STREQUAL "Windows")
       # Windows x86/x64
+    elseif (TARGET_OS STREQUAL "Darwin")
+      add_definitions(-DSPEC_MACOSX)
     else ()
       message("ARCH: ${ARCH}")
       message("TARGET_OS: ${TARGET_OS}")