diff --git a/src/ioc/db/callback.c b/src/ioc/db/callback.c
index 2a4a291cc..76fb154b7 100644
--- a/src/ioc/db/callback.c
+++ b/src/ioc/db/callback.c
@@ -63,7 +63,7 @@ static cbQueueSet callbackQueue[NUM_CALLBACK_PRIORITIES];
 int callbackThreadsDefault = 1;
 /* Don't know what a reasonable default is (yet).
  * For the time being: parallel means 2 if not explicitly specified */
-int callbackParallelThreadsDefault = 2;
+epicsShareDef int callbackParallelThreadsDefault = 2;
 epicsExportAddress(int,callbackParallelThreadsDefault);
 
 /* Timer for Delayed Requests */
diff --git a/src/ioc/db/dbIocRegister.c b/src/ioc/db/dbIocRegister.c
index 7ef15ac1f..8b4be4fd9 100644
--- a/src/ioc/db/dbIocRegister.c
+++ b/src/ioc/db/dbIocRegister.c
@@ -23,7 +23,7 @@
 #include "dbIocRegister.h"
 #include "dbState.h"
 
-epicsShareDef int callbackParallelThreadsDefault;
+epicsShareExtern int callbackParallelThreadsDefault;
 
 /* dbLoadDatabase */
 static const iocshArg dbLoadDatabaseArg0 = { "file name",iocshArgString};