diff --git a/src/libCom/osi/os/RTEMS/osdTime.cpp b/src/libCom/osi/os/RTEMS/osdTime.cpp
index 6dd0aa4be..7408d3aa7 100644
--- a/src/libCom/osi/os/RTEMS/osdTime.cpp
+++ b/src/libCom/osi/os/RTEMS/osdTime.cpp
@@ -11,12 +11,13 @@
  */
 //
 
+#include <rtems.h>
 #include "epicsTime.h"
 #include "osiNTPTime.h"
 #include "osdSysTime.h"
 #include "generalTimeSup.h"
 
-extern int rtems_bsdnet_get_ntp(int, int(*)(), struct timespec *);
+extern "C" int rtems_bsdnet_get_ntp(int, int(*)(), struct timespec *);
 
 extern "C" epicsShareFunc int epicsShareAPI osdTimeInit(void)
 {
diff --git a/src/libCom/osi/osiNTPTime.c b/src/libCom/osi/osiNTPTime.c
index 0f75938ff..0de52e29d 100644
--- a/src/libCom/osi/osiNTPTime.c
+++ b/src/libCom/osi/osiNTPTime.c
@@ -78,7 +78,7 @@ static void NTPTimeSyncNTP(void)
                 errlogPrintf("NTPTimeSyncWithNTPserver: sntpcTimeGet %s\n",
                     strerror(errno));
             prevStatusBad = 1;
-            pNTPTimePvt->synced = FALSE;
+            pNTPTimePvt->synced = 0;
             continue;
         }
         nConsecutiveBad=0;
@@ -96,7 +96,7 @@ static void NTPTimeSyncNTP(void)
             pNTPTimePvt->ticksToSkip = (int) ((-1)*diffTime*pNTPTimePvt->tickRate);/* fix bug here */
         }
         pNTPTimePvt->lastTick = tickGet();
-        pNTPTimePvt->synced = TRUE;
+        pNTPTimePvt->synced = 1;
         epicsMutexUnlock(pNTPTimePvt->lock);
     }
 }
@@ -109,7 +109,7 @@ static long NTPTime_InitOnce(int priority)
 
     pNTPTimePvt = callocMustSucceed(1,sizeof(NTPTimePvt),"NTPTime_Init");
 
-    pNTPTimePvt->synced = FALSE;
+    pNTPTimePvt->synced = 0;
     pNTPTimePvt->lock = epicsMutexCreate();
     pNTPTimePvt->nanosecondsPerTick = BILLION/sysClkRateGet();
     pNTPTimePvt->tickRate = sysClkRateGet();
@@ -138,7 +138,7 @@ static long NTPTime_InitOnce(int priority)
         epicsMutexMustLock(pNTPTimePvt->lock);
         pNTPTimePvt->clock = epicsTime;
         pNTPTimePvt->lastTick = tickGet();
-        pNTPTimePvt->synced = TRUE;
+        pNTPTimePvt->synced = 1;
         epicsMutexUnlock(pNTPTimePvt->lock);
         printf("First try to sync with NTP server succeed!\n");
     }