problem using integer division in kernel modules

problem using integer division in kernel modules

[Thomas Schlichter]

Hi,

I am writing at a small kernel module and have a problem now using / and %. If 
I do so I get following unresolved symbols when the module should be loaded:
  __divdi3
  __moddi3

Could you please help me and tell me what I do wrong..?

Re: problem using integer division in kernel modules

[Matti Aarnio]

On Wed, Jan 15, 2003 at 07:41:29PM +0100, Thomas Schlichter wrote:
> Hi,
> 
> I am writing at a small kernel module and have a problem now using / and %. If 
> I do so I get following unresolved symbols when the module should be loaded:
>   __divdi3
>   __moddi3

  64-bit division with non-constant non-power-of-two divider.

> Could you please help me and tell me what I do wrong..?

  The kernel is linked without gcc builtin libraries.
  Reasons can be found from FAQ (see footer), or archives.

/Matti Aarnio

Re: problem using integer division in kernel modules

[george anzinger]

Matti Aarnio wrote:
> 
> On Wed, Jan 15, 2003 at 07:41:29PM +0100, Thomas Schlichter wrote:
> > Hi,
> >
> > I am writing at a small kernel module and have a problem now using / and %. If
> > I do so I get following unresolved symbols when the module should be loaded:
> >   __divdi3
> >   __moddi3
> 
>   64-bit division with non-constant non-power-of-two divider.
> 
> > Could you please help me and tell me what I do wrong..?
> 
>   The kernel is linked without gcc builtin libraries.
>   Reasons can be found from FAQ (see footer), or archives.

You may want to check out .../include/asm-???/div64.h.  It
allows some limited divides with 64-bit numbers.  Look at
several so you understand what it does and does not do.

-g
> 
> /Matti Aarnio
> -
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