Re: Warnings from sched_debug.c

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



* Meelis Roos <[email protected]> wrote:

> This happens on sparc64 with 2.6.24-rc6 (gcc-4.2):
> 
>   CC      kernel/sched.o
> In file included from kernel/sched.c:879:
> kernel/sched_debug.c: In function 'nsec_high':
> kernel/sched_debug.c:38: warning: comparison of distinct pointer types lacks a cast
> kernel/sched_debug.c:41: warning: comparison of distinct pointer types lacks a cast
> kernel/sched_debug.c: In function 'nsec_low':
> kernel/sched_debug.c:51: warning: comparison of distinct pointer types lacks a cast

it should be harmless. Does the patch below fix the warnings?

	Ingo

-------------->
Subject: sched: fix gcc warnings
From: Ingo Molnar <[email protected]>

Meelis Roos reported these warnings on sparc64:

  CC      kernel/sched.o
  In file included from kernel/sched.c:879:
  kernel/sched_debug.c: In function 'nsec_high':
  kernel/sched_debug.c:38: warning: comparison of distinct pointer types lacks a cast

the debug check in do_div() is over-eager here, because the long long
is always positive in these places. Mark this by casting them to
unsigned long long.

no change in code output:

   text    data     bss     dec     hex filename
  51471    6582     376   58429    e43d sched.o.before
  51471    6582     376   58429    e43d sched.o.after

  md5:
   7f7729c111f185bf3ccea4d542abc049  sched.o.before.asm
   7f7729c111f185bf3ccea4d542abc049  sched.o.after.asm

Signed-off-by: Ingo Molnar <[email protected]>
---
 kernel/sched_debug.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Index: linux/kernel/sched_debug.c
===================================================================
--- linux.orig/kernel/sched_debug.c
+++ linux/kernel/sched_debug.c
@@ -31,9 +31,9 @@
 /*
  * Ease the printing of nsec fields:
  */
-static long long nsec_high(long long nsec)
+static long long nsec_high(unsigned long long nsec)
 {
-	if (nsec < 0) {
+	if ((long long)nsec < 0) {
 		nsec = -nsec;
 		do_div(nsec, 1000000);
 		return -nsec;
@@ -43,9 +43,9 @@ static long long nsec_high(long long nse
 	return nsec;
 }
 
-static unsigned long nsec_low(long long nsec)
+static unsigned long nsec_low(unsigned long long nsec)
 {
-	if (nsec < 0)
+	if ((long long)nsec < 0)
 		nsec = -nsec;
 
 	return do_div(nsec, 1000000);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux