diff --git a/src/libCom/osi/osiSem.h b/src/libCom/osi/osiSem.h
index 64e7f4503..1ce3617cf 100644
--- a/src/libCom/osi/osiSem.h
+++ b/src/libCom/osi/osiSem.h
@@ -42,6 +42,16 @@ epicsShareFunc void epicsShareAPI semMutexShow(semMutexId id);
     Mutex semaphores should implement priority inheritance and deletion safe
 */
 
+#ifdef __cplusplus
+}
+#endif
+
+#include "osdSem.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 epicsShareFunc INLINE semBinaryId epicsShareAPI semBinaryMustCreate (
     int initialState)
 {
@@ -71,7 +81,4 @@ epicsShareFunc INLINE void epicsShareAPI semMutexMustTake(semMutexId id)
 }
 #endif
 
-#include "osdSem.h"
-
-
 #endif /* osiSemh */