# Kernel compilation probs.

## +BroNNoS+

Hi all,

I was strolling around in my kernel settings and saw that it was configured for SMP, but I've got only one processor (PIII) so I thought let's disable it. But now the compilation fails. Turned it back on, compilation goes well again. Hmmmm...this is what I get:

In file included from ksyms.c:17:

/usr/src/linux-2.4.19-r1/include/linux/kernel_stat.h: In function `kstat_irqs':

/usr/src/linux-2.4.19-r1/include/linux/kernel_stat.h:50: `smp_num_cpus' undeclared (first use in this function)

/usr/src/linux-2.4.19-r1/include/linux/kernel_stat.h:50: (Each undeclared identifier is reported only once

/usr/src/linux-2.4.19-r1/include/linux/kernel_stat.h:50: for each function it appears in.)

make[2]: *** [ksyms.o] Error 1

make[2]: Leaving directory `/usr/src/linux-2.4.19-r1/kernel'

make[1]: *** [first_rule] Error 2

make[1]: Leaving directory `/usr/src/linux-2.4.19-r1/kernel'

make: *** [_dir_kernel] Error 2

It's talking about : `smp_num_cpus' undeclared. Looks like something is still expecting the number of cpu's here. But I only got one. Any idea's?

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## Fragadelic

What options do have set for the Processor section?

Did you remember to do a 'make dep' and then a 'make clean' before doing the 'make bzImage'?

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## fghellar

You also need to do a 'make mrproper'. (Check here)

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## +BroNNoS+

This is what I tried: 

(Pentium-III/Celeron(Coppermine)) Processor family

     [*] Machine Check Exception

    < > Toshiba Laptop support

    < > Dell laptop support

    < > /dev/cpu/microcode - Intel IA32 CPU microcode support

    < > /dev/cpu/*/msr - Model-specific register support

    < > /dev/cpu/*/cpuid - CPU information support

   (off) High Memory Support

    [ ] Math emulation

    [ ] MTRR (Memory Type Range Register) support

    [ ] Symmetric multi-processing support

    [ ] Local APIC support on uniprocessors (NEW)

And I tried changing various setting here, but I have to select Symmetric multi-processing support to get the kernel to compile.

And I issue the normal:

make dep && make clean bzImage modules modules_install

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## Fragadelic

 *fghellar wrote:*   

> You also need to do a 'make mrproper'. (Check here)

 

That is it!  I couldn't remember exactly what brought it all back to standard base but you have it.

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