64bit kernel on 32bit clusters

scolari · n00b Joined: 04 Feb 2008 Posts: 4

Hello,

We have a cluster of machines, this cluster is getting old so we replace machines with new ones. The cluster is mainly made of athlon-xp and athlon-64. Up to now we mantained 32 bit for both the user space and kernel for the entire cluster. Yesterday we tried to compile a 64 bit kernel for the sparkling new 64 bit machine but we din't succeded. In fact the gcc compiler have an -m64 option but it give the following error:

sorry, unimplemented: 64-bit mode not compiled in

Searching the web we found that this error is the normality for gcc 32-bit. We also found that some gcc (the debian ones) can compiles -m64 also in 32-bit modes. This option can be very usefull and we will not need to install a cross-compiler.
Is there some option in Gentoo to build such this compiler? I heard there is a patch somewere, can someone point me some direction?

Thanks!

DarkGian · n00b Joined: 31 Oct 2007 Posts: 3

Hi everybody, I am one of scolari's colleagues.
It may be a little OT since the question seems more focused on the -m64 option of gcc, but I thought of of trying the gentoo way and emerging crossdev. I followed step by step what written in the Gentoo Embedded Handbook and managed to create my sysroot for the tuple x86_64-unknown-linux-gnu, with crossdev working just fine. I then succeded "xmerging" vanilla-sources, but in the final phase, while actually building the kernel, I get the weird error: