Building old systems

[Brook Milligan <brook%nmsu.edu@localhost>]

I am trying to build an old kernel with build.sh on a recent (9.99.108) amd64 system.  However, compiling nbmake fails immediately with errors like

	/usr/bin/ld: buf.o:(.bss+0x0): multiple definition of `debug_file'; arch.o:(.bss+0x0): first defined here 

Unless I am doing something silly, it clearly is not possible for a current system to build old tools and kernels at arbitrary points in time.

What is the best strategy for building old kernels to, for example, bisect the code?

Cheers,
Brook