[src/trunk]: src/sys/kern Cast argument to uint64_t first before shifting to ...

[joerg <joerg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b077b96e0acf
branches:  trunk
changeset: 341813:b077b96e0acf
user:      joerg <joerg%NetBSD.org@localhost>
date:      Mon Nov 23 23:45:44 2015 +0000

description:
Cast argument to uint64_t first before shifting to avoid UB for
left-shifting negative values.

diffstat:

 sys/kern/kern_ntptime.c |  6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diffs (27 lines):

diff -r fddfe423f283 -r b077b96e0acf sys/kern/kern_ntptime.c
--- a/sys/kern/kern_ntptime.c   Mon Nov 23 23:28:33 2015 +0000
+++ b/sys/kern/kern_ntptime.c   Mon Nov 23 23:45:44 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_ntptime.c,v 1.56 2015/07/24 13:02:52 maxv Exp $   */
+/*     $NetBSD: kern_ntptime.c,v 1.57 2015/11/23 23:45:44 joerg Exp $  */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -60,7 +60,7 @@
 
 #include <sys/cdefs.h>
 /* __FBSDID("$FreeBSD: src/sys/kern/kern_ntptime.c,v 1.59 2005/05/28 14:34:41 rwatson Exp $"); */
-__KERNEL_RCSID(0, "$NetBSD: kern_ntptime.c,v 1.56 2015/07/24 13:02:52 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_ntptime.c,v 1.57 2015/11/23 23:45:44 joerg Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ntp.h"
@@ -99,7 +99,7 @@
 #define L_MPY(v, a)    ((v) *= (a))
 #define L_CLR(v)       ((v) = 0)
 #define L_ISNEG(v)     ((v) < 0)
-#define L_LINT(v, a)   ((v) = (int64_t)(a) << 32)
+#define L_LINT(v, a)   ((v) = (int64_t)((uint64_t)(a) << 32))
 #define L_GINT(v)      ((v) < 0 ? -(-(v) >> 32) : (v) >> 32)
 
 #ifdef NTP