lkml.org 
[lkml]   [2004]   [Nov]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [2.6 patch] kill IN_STRING_C
On Mon, Nov 08, 2004 at 07:04:13PM +0100, Pawe?? Sikora wrote:
> On Monday 08 of November 2004 17:31, you wrote:
> > On Mon, Nov 08, 2004 at 05:19:35PM +0100, Andi Kleen wrote:
> > > > Rethinking it, I don't even understand the sprintf example in your
> > > > changelog entry - shouldn't an inclusion of kernel.h always get it
> > > > right?
> > >
> > > Newer gcc rewrites sprintf(buf,"%s",str) to strcpy(buf,str)
> > > transparently.
> >
> > Which gcc is "Newer"?
> >
> > My gcc 3.4.2 didn't show this problem.
>
> #include <stdio.h>
> #include <string.h>
> char buf[128];
> void test(char *str)
> {
> sprintf(buf, "%s", str);
> }
>...
> jmp strcpy
>...


This is the userspace example.

The kernel example is:

#include <linux/string.h>
#include <linux/kernel.h>

char buf[128];
void test(char *str)
{
sprintf(buf, "%s", str);
}


This results with gcc-3.4 (GCC) 3.4.2 (Debian 3.4.2-3) in:

.file "test.c"
.section .rodata.str1.1,"aMS",@progbits,1
.LC0:
.string "%s"
.text
.p2align 4,,15
.globl test
.type test, @function
test:
pushl %eax
pushl $.LC0
pushl $buf
call sprintf
addl $12, %esp
ret
.size test, .-test
.globl buf
.bss
.align 32
.type buf, @object
.size buf, 128
buf:
.zero 128
.section .note.GNU-stack,"",@progbits
.ident "GCC: (GNU) 3.4.2 (Debian 3.4.2-3)"



cu
Adrian

--

"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:07    [W:0.061 / U:0.376 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site