Re: 64 bit arithmetic in the kernel

Michael Richardson (mcr@solidum.com)
Wed, 14 Jul 1999 15:35:22 -0400


>>>>> "Nat" == Nat Lanza <magus@cs.cmu.edu> writes:
Nat> Michael Richardson <mcr@solidum.com> writes:

>> Is there any easy way to get things like the stuff that it
>> is in libgcc1.a into the Linux kernel? I have need for 64/32 integer divide
>> (gcc calls __udivdi3).
>> This is with 2.2.10, on a Lintel box, and I'm using a module.
>>
>> I noticed that printk() doesn't have support for 64 bit quantities either.

Nat> We got around this by simply linking libgcc into the kernel; it seems
Nat> to work okay for 64-bit arithmetic.

This worked wonderfully, and I thank the several people who suggested that
I could just use "ld -r" to do this. Why isn't libgcc1.a linked into the
kernel somewhere when compiling with GCC already? Or are the symbols not
exported perhaps?

Nat> Also, patching printk so that it supports 64-bit quantities is pretty
Nat> simple; I have a patch against 2.2.3 for that that I'll clean up and
Nat> redo for 2.2.10 and then post.

Thanks, I appreciate this. I was about to do it, but my answer is all I
need to print.

:!mcr!: | Solidum Systems Corporation, http://www.solidum.com
Michael Richardson |For a better connected world,where data flows faster<tm>
Personal: <A HREF="http://www.sandelman.ottawa.on.ca/People/Michael_Richardson/Bio.html">mcr@sandelman.ottawa.on.ca</A>. PGP key available.
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