[PATCH] Prevent usage of uninitialized variable in transmeta cpu driver

[PATCH] Prevent usage of uninitialized variable in transmeta cpu driver

[Johannes Weiner]

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This patch fixes a gcc-`uninitialized' warning in
arch/i386/kernel/cpu/transmeta.c.

Signed-off-by: Johannes Weiner <hnazfoo@gmail.com>

---

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diff --git a/arch/i386/kernel/cpu/transmeta.c b/arch/i386/kernel/cpu/transmeta.c
index 7214c9b..5b71071 100644
--- a/arch/i386/kernel/cpu/transmeta.c
+++ b/arch/i386/kernel/cpu/transmeta.c
@@ -17,9 +17,9 @@ static void __init init_transmeta(struct
 
 	/* Print CMS and CPU revision */
 	max = cpuid_eax(0x80860000);
-	cpu_rev = 0;
+	cpu_rev = cpu_freq = 0;
 	if ( max >= 0x80860001 ) {
-		cpuid(0x80860001, &dummy, &cpu_rev, &cpu_freq, &cpu_flags); 
+		cpuid(0x80860001, &dummy, &cpu_rev, &cpu_freq, &cpu_flags);
 		if (cpu_rev != 0x02000000) {
 			printk(KERN_INFO "CPU: Processor revision %u.%u.%u.%u, %u MHz\n",
 				(cpu_rev >> 24) & 0xff,
@@ -72,7 +72,7 @@ static void __init init_transmeta(struct
 	wrmsr(0x80860004, ~0, uk);
 	c->x86_capability[0] = cpuid_edx(0x00000001);
 	wrmsr(0x80860004, cap_mask, uk);
-	
+
 	/* If we can run i686 user-space code, call us an i686 */
 #define USER686 (X86_FEATURE_TSC|X86_FEATURE_CX8|X86_FEATURE_CMOV)
         if ( c->x86 == 5 && (c->x86_capability[0] & USER686) == USER686 )

Re: [PATCH] Prevent usage of uninitialized variable in transmeta cpu driver

[Jiri Slaby]

Johannes Weiner napsal(a):
> This patch fixes a gcc-`uninitialized' warning in
> arch/i386/kernel/cpu/transmeta.c.

NACK.

Gcc bug, don't hide it (I don't really know, why cpu_rev is zeroed).

[Post only whitespace changes. And note that such changes should be in separated
patches.]

> 
> Signed-off-by: Johannes Weiner <hnazfoo@gmail.com>
> 
> ---
> 
> 
> ------------------------------------------------------------------------
> 
> diff --git a/arch/i386/kernel/cpu/transmeta.c b/arch/i386/kernel/cpu/transmeta.c
> index 7214c9b..5b71071 100644
> --- a/arch/i386/kernel/cpu/transmeta.c
> +++ b/arch/i386/kernel/cpu/transmeta.c
> @@ -17,9 +17,9 @@ static void __init init_transmeta(struct
>  
>  	/* Print CMS and CPU revision */
>  	max = cpuid_eax(0x80860000);
> -	cpu_rev = 0;
> +	cpu_rev = cpu_freq = 0;
>  	if ( max >= 0x80860001 ) {
> -		cpuid(0x80860001, &dummy, &cpu_rev, &cpu_freq, &cpu_flags); 
> +		cpuid(0x80860001, &dummy, &cpu_rev, &cpu_freq, &cpu_flags);
>  		if (cpu_rev != 0x02000000) {
>  			printk(KERN_INFO "CPU: Processor revision %u.%u.%u.%u, %u MHz\n",
>  				(cpu_rev >> 24) & 0xff,
> @@ -72,7 +72,7 @@ static void __init init_transmeta(struct
>  	wrmsr(0x80860004, ~0, uk);
>  	c->x86_capability[0] = cpuid_edx(0x00000001);
>  	wrmsr(0x80860004, cap_mask, uk);
> -	
> +
>  	/* If we can run i686 user-space code, call us an i686 */
>  #define USER686 (X86_FEATURE_TSC|X86_FEATURE_CX8|X86_FEATURE_CMOV)
>          if ( c->x86 == 5 && (c->x86_capability[0] & USER686) == USER686 )

regards,
-- 
<a href="http://www.fi.muni.cz/~xslaby/">Jiri Slaby</a>
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E

Re: [PATCH] Prevent usage of uninitialized variable in transmeta cpu driver

[Johannes Weiner]

Hi,

On Mon, Jul 24, 2006 at 01:56:44AM +0159, Jiri Slaby wrote:
> Johannes Weiner napsal(a):
> > This patch fixes a gcc-`uninitialized' warning in
> > arch/i386/kernel/cpu/transmeta.c.
> 
> NACK.
> 
> Gcc bug, don't hide it (I don't really know, why cpu_rev is zeroed).

Ok. This GCC release I'm running (4.1.1) shows really a lot more of
them then the prior. Should have wondered and thought about it before ;)

Hannes

-- 
#include <stdio.h>
char *love[] = { "this", "language" };
#define gimme(s) #s, 0[s], 0[s+1]
int main(void) { printf("%s %s %s\n", gimme(love)); return 0; }