diff --git a/src/fontdetection.cpp b/src/fontdetection.cpp
--- a/src/fontdetection.cpp
+++ b/src/fontdetection.cpp
@@ -396,7 +396,7 @@ FT_Error GetFontByFaceName(const char *f
 	} else
 #endif
 	{
-#if (MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5) && !__LP64__
+#if (MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_5) && !defined(__LP64__)
 		/* This type was introduced with the 10.5 SDK. */
 #if (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_5)
 	#define ATSFSSpec FSSpec