diff --git a/src/common/mac/macho_id.cc b/src/common/mac/macho_id.cc
index 728bd47e..160f6ed7 100644
--- a/src/common/mac/macho_id.cc
+++ b/src/common/mac/macho_id.cc
@@ -33,17 +33,19 @@
 //
 // Author: Dan Waylonis
 
-#include <fcntl.h>
-#include <mach-o/loader.h>
-#include <mach-o/swap.h>
-#include <openssl/md5.h>
-#include <openssl/sha.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <unistd.h>
+extern "C" {  // necessary for Leopard
+  #include <fcntl.h>
+  #include <mach-o/loader.h>
+  #include <mach-o/swap.h>
+  #include <openssl/md5.h>
+  #include <openssl/sha.h>
+  #include <stdio.h>
+  #include <stdlib.h>
+  #include <string.h>
+  #include <sys/time.h>
+  #include <sys/types.h>
+  #include <unistd.h>
+}
 
 #include "common/mac/macho_id.h"
 #include "common/mac/macho_walker.h"