diff --git a/src/WINNT/client_osi/osilog.h b/src/WINNT/client_osi/osilog.h
index e186712a0a..c2a6ff4188 100644
--- a/src/WINNT/client_osi/osilog.h
+++ b/src/WINNT/client_osi/osilog.h
@@ -24,7 +24,7 @@ typedef struct osi_logEntry {
 	size_t tid;			/* thread ID */
         unsigned long micros;		/* microsecond-based time stamp */
         char *formatp;			/* format string */
-        long parms[OSI_LOG_MAXPARMS];	/* parms */
+        size_t parms[OSI_LOG_MAXPARMS];	/* parms */
 } osi_logEntry_t;
 
 typedef struct osi_log {