blog.crox.net

I wanted to try the new 2.6.25 kernel on a Sunblade 100 I'm reinstalling. But immediately after entering "make" I got the following error:

arch/sparc64/kernel/asm-offsets.c:1: error: -m64 is not supported by this configuration
arch/sparc64/kernel/asm-offsets.c:1: error: -mlong-double-64 not allowed with -m64
arch/sparc64/kernel/asm-offsets.c:1: error: -mcmodel= is not supported on 32 bit systems
make[1]: *** [arch/sparc64/kernel/asm-offsets.s] Error 1
make: *** [prepare0] Error 2

I found the solution here, along with the explanation. To make it short, to get it to work, for now you'll have to type:

 # CROSS_COMPILE=sparc64-unknown-linux-gnu- make

If you get this:

[blocks B ] sys-devel/gcc-sparc64 (is blocking sys-devel/kgcc64-3.4.6)

Check this thread on the gentoo forums:

There are a couple of architectures on Gentoo that have a 32-bit userland, but need a 64-bit kernel compiler. kgcc64 is an attempt to provide one package for all of those architectures rather than the gcc- packages that exist now. The way we migrated over to this caused the issue you are seeing.

Basically, you'll need to

emerge --unmerge gcc-sparc64 && emerge sys-devel/kgcc64