[PATCH] Compile warning because of an uninitialized variable

[PATCH] Compile warning because of an uninitialized variable

[Stephane Ouellette]

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Folks,

    gcc generates a warning because of an uninitialized variable in arch/i386/kernel/cpu/transmeta.c.
The variable "cpu_freq" is initialized by a call to cpuid(). The following patch fixes the warning.

Regards,

Stephane.

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--- linux-2.6.16.16/arch/i386/kernel/cpu/transmeta.c	2006-05-04 20:03:45.000000000 -0400
+++ linux-2.6.16.16-fixed/arch/i386/kernel/cpu/transmeta.c	2006-05-18 15:19:52.000000000 -0400
@@ -18,6 +18,7 @@
 	/* Print CMS and CPU revision */
 	max = cpuid_eax(0x80860000);
 	cpu_rev = 0;
+	cpu_freq = 0;
 	if ( max >= 0x80860001 ) {
 		cpuid(0x80860001, &dummy, &cpu_rev, &cpu_freq, &cpu_flags); 
 		if (cpu_rev != 0x02000000) {

Re: [PATCH] Compile warning because of an uninitialized variable

[Dave Jones]

On Thu, May 18, 2006 at 11:49:25PM -0400, Stephane Ouellette wrote:
 > Folks,
 > 
 >    gcc generates a warning because of an uninitialized variable in 
 >    arch/i386/kernel/cpu/transmeta.c.
 > The variable "cpu_freq" is initialized by a call to cpuid(). The following 
 > patch fixes the warning.

This is a gcc bug. The variable is passed by reference
to a function where the assignment is made.
The second time it's used, if that > 80860002 condition
is satisfied, we *must* have satisfied the previous
check where we made the assignment, as 'max' hasn't changed
between the two checks.

		Dave

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