diff --git a/harbour/contrib/libct/strswap.c b/harbour/contrib/libct/strswap.c
index d07b8d856c..bfa1f11f9b 100644
--- a/harbour/contrib/libct/strswap.c
+++ b/harbour/contrib/libct/strswap.c
@@ -96,7 +96,7 @@ HB_FUNC (STRSWAP)
     /* get parameters */
     char *pcString1 = (char *)hb_parc (1);
     char *pcString2 = (char *)hb_parc (2);
-    char *pcRet1, *pcRet2;
+    char *pcRet1 = NULL, *pcRet2 = NULL;
     int iChange1, iChange2;
     size_t sIndex, sCmpLen;