diff --git a/src/hb-common.h b/src/hb-common.h
index 2532d69fe..ae23698a5 100644
--- a/src/hb-common.h
+++ b/src/hb-common.h
@@ -33,6 +33,10 @@
 #ifndef HB_COMMON_H
 #define HB_COMMON_H
 
+#ifndef HB_EXTERN
+#define HB_EXTERN extern
+#endif
+
 #ifndef HB_BEGIN_DECLS
 # ifdef __cplusplus
 #  define HB_BEGIN_DECLS	extern "C" {
diff --git a/src/hb.h b/src/hb.h
index fc75a6918..c5e7072fb 100644
--- a/src/hb.h
+++ b/src/hb.h
@@ -28,10 +28,6 @@
 #define HB_H
 #define HB_H_IN
 
-#ifndef HB_EXTERN
-#define HB_EXTERN extern
-#endif
-
 #include "hb-blob.h"
 #include "hb-buffer.h"
 #include "hb-common.h"