On Wed, Apr 19, 2023 at 16:34:19 -0600, Brook Milligan wrote: > 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?
It might be better to use corresponding older tools to build older kernels. Modern gcc switched to -fno-common by default, so if you want to compile an older kernel that has multiple variable definitions you will need to arrange for -fcommon option to be used. -uwe
