diff --git a/CMakeLists.txt b/CMakeLists.txt
index 55c92992a..74eda636a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -194,7 +194,8 @@ if(UNIX)
     }" HAVE_RLIMIT_CORE)
 
   if(APPLE)
-    check_cxx_source_compiles("#include <sys/ptrace.h>
+    check_cxx_source_compiles("#include <sys/types.h>
+      #include <sys/ptrace.h>
       int main() { ptrace(PT_DENY_ATTACH, 0, 0, 0); return 0; }"
       HAVE_PT_DENY_ATTACH)
   endif()
diff --git a/src/core/Tools.cpp b/src/core/Tools.cpp
index 5d1d6e2c9..ab4bec0bd 100644
--- a/src/core/Tools.cpp
+++ b/src/core/Tools.cpp
@@ -46,6 +46,7 @@
 #endif
 
 #ifdef HAVE_PT_DENY_ATTACH
+#include <sys/types.h>
 #include <sys/ptrace.h>
 #endif