diff --git a/tests/randomcheck.c b/tests/randomcheck.c
index d605b60..560284d 100644
--- a/tests/randomcheck.c
+++ b/tests/randomcheck.c
@@ -46,7 +46,7 @@ static void run_randomtest( unsigned short (*keygen)(void) )
     unsigned short rnd;
 
     /* zero bitcount first */
-    memset(bitcount,0,16*sizeof(int));
+    memset(bitcount, 0, sizeof(bitcount));
 
     for(i=0;i<rounds;i++)
     {