diff --git a/library/x509parse.c b/library/x509parse.c
index ddbeb38..c6a9245 100644
--- a/library/x509parse.c
+++ b/library/x509parse.c
@@ -2411,7 +2411,7 @@
     SAFE_SNPRINTF();
 
     ret = snprintf( p, n, "\n%sRSA key size  : %d bits\n", prefix,
-                   crt->rsa.N.n * (int) sizeof( unsigned long ) * 8 );
+                   (int) crt->rsa.N.n * (int) sizeof( unsigned long ) * 8 );
     SAFE_SNPRINTF();
 
     return( (int) ( size - n ) );