diff --git a/modules/libcom/src/error/errSymLib.c b/modules/libcom/src/error/errSymLib.c
index d81705068..5f329ac9a 100644
--- a/modules/libcom/src/error/errSymLib.c
+++ b/modules/libcom/src/error/errSymLib.c
@@ -23,6 +23,7 @@
 #include "cantProceed.h"
 #include "epicsAssert.h"
 #include "epicsStdio.h"
+#include "epicsTypes.h"
 #include "epicsMutex.h"
 #include "epicsThread.h"
 #include "errMdef.h"