diff --git a/devS7plcFW.c b/devS7plcFW.c
index 7631269..b42afa5 100644
--- a/devS7plcFW.c
+++ b/devS7plcFW.c
@@ -1761,7 +1761,7 @@ STATIC long s7plcFWReadAi(aiRecord *record)
         case epicsFloat64T:
             status = s7plcFWRead(priv->station, priv->offs,
                 8, &val64);
-            __extension__ s7plcFWDebugLog(3, "ai %s: read 64bit %08Lx = %g\n",
+            __extension__ s7plcFWDebugLog(3, "ai %s: read 64bit " CONV64 " = %g\n",
                 record->name, val64.i, val64.f);
             floatval = TRUE;
             break;
@@ -2025,7 +2025,7 @@ STATIC long s7plcFWInitRecordStringin(stringinRecord *record)
     {
         errlogSevPrintf(errlogMinor,
             "%s: string size reduced from %d to %d\n",
-            record->name, priv->dlen, sizeof(record->val));
+            record->name, priv->dlen, (int)sizeof(record->val));
         priv->dlen = sizeof(record->val);
     }
     record->dpvt = priv;
@@ -2105,7 +2105,7 @@ STATIC long s7plcFWInitRecordStringout(stringoutRecord *record)
     {
         errlogSevPrintf(errlogMinor,
             "%s: string size reduced from %d to %d\n",
-            record->name, priv->dlen, sizeof(record->val));
+            record->name, priv->dlen, (int)sizeof(record->val));
         priv->dlen = sizeof(record->val);
     }
     record->dpvt = priv;