kernel module and float

[Jean-Yves Moulin]

Hello,

I have a problem with gcc on amd64 platform. I need to do division and 
multiplication with float into a kernel module. This module compile, 
load and run without problem on i386 platform. I can compile it on amd64 
but when I try to load it I have:

link_elf_obj: symbol __mulsf3 undefined

After some search, I found that __mulsf3 (and __divsf3...etc) are 
builtin function of gcc. In my assembly source result, I have a "call 
__mulsf3" but the function is defined nowhere.

I'm working on amd64 6.3-RELEASE binaries and source tree.


Is that normal ? Do I need to use something special in order to use 
float into kernel ? How can I solve this ?

Thanks in advance for your help

Best regards,
jym