Building 6.8.0-7 was possible. Building 6.8.0-9 fails - but I changed a few things:
added LLVM=1 and removed it later on (then debain/rules clean 'ed),
installed lib*-dev based on "Auto-detecting system features" output,
KBUILD_BUILD_TIMESTAMP='2024-02-13'
CC='ccache cc'
Building 6.8.0-7 was possible. Building 6.8.0-9 fails - but I changed a few things: BUILD_TIMESTAMP ='2024- 02-13'
added LLVM=1 and removed it later on (then debain/rules clean 'ed),
installed lib*-dev based on "Auto-detecting system features" output,
KBUILD_
CC='ccache cc'