As far as I know, coreboot runs in 32-bit mode on the x86 architecture,
even if the hardware supports x86_64. This does not prevent running x86_64
Therefore, and as the first document you linked says, you should build the
i386 toolchain and build coreboot with it.
Angel Pons Pons
On Sun, Aug 19, 2018 at 8:43 PM, <hybris(a)e2m.io> wrote:
I am trying to build coreboot for a Lenovo Thinkpad x201.
I followed the instructions from the following documents:
When using the crossgcc-x64 toolchain building works fine but linking
fails with the following error:
coreboot/src/console/vtxprintf.c:102: undefined reference to
As far is i could find out this error should not even get thrown for x64,
since `__udivmoddi4` is an optimization for i386. 
Building (and linking) with the crossgcc-i386 toolchain works fine though.
But I guess x64 features will then be missing in the build.
Is there currently a way to build a x64 version of coreboot or do I have
to go with i386 for now?
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