[PATCH] Compile failure fix for ppc on 2.6.17-rc4-mm3 (2nd attempt)

Segher Boessenkool segher at kernel.crashing.org
Tue May 30 02:22:33 EST 2006


>>>  arch/powerpc/kernel/built-in.o(.init.text+0x77b4): In function 
>>> `vrsqrtefp':
>>>  : undefined reference to `__udivdi3'
>>>  arch/powerpc/kernel/built-in.o(.init.text+0x7800): In function 
>>> `vrsqrtefp':
>>>  : undefined reference to `__udivdi3'
>>>  make: *** [.tmp_vmlinux1] Error 1
>>
>> A function with a name like that doesn't _deserve_ to compile.

Would vector_reciprocal_square_root_estimate_floating_point() be any 
better...
Anyway, this is just a machine insn mnemonic, so the function name is 
fine
I believe.

>  #define push_end(res, size) do { unsigned long __sz = (size) ; \
> -	res->end = ((res->end + __sz) / (__sz + 1)) * (__sz + 1) + __sz; \
> +	resource_size_t farEnd = (res->end + __sz); \
> +	do_div(farEnd, (__sz + 1)); \
> +	res->end = farEnd * (__sz + 1) + __sz; \
>      } while (0)

Size here is a) a misnomer (size + 1 is the actual size) and b) always 
a power
of two minus one.  So instead, do

#define push_end(res, mask) res->end = -(-res->end & ~(unsigned 
long)mask)

(with a do { } while(0) armour if you prefer).


Segher




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