At present the kselftest header can't be used with nolibc since it makes use of vprintf() which is not available in nolibc and seems like it would be inappropriate to implement given the minimal system requirements and environment intended for nolibc. This has resulted in some open coded kselftests which use nolibc to test features that are supposed to be controlled via libc and therefore better exercised in an environment with no libc. Rather than continue this let's factor out the I/O routines in kselftest.h into a separate header file and provide a nolibc implementation which only allows simple strings to be provided rather than full printf() support. This is limiting but a great improvement on sharing no code at all. As an example of using this I've updated the arm64 za-fork test to use the standard kselftest.h. Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- Mark Brown (2): kselftest: Support nolibc kselftest/arm64: Convert za-fork to use kselftest.h tools/testing/selftests/arm64/fp/Makefile | 2 +- tools/testing/selftests/arm64/fp/za-fork.c | 88 +++-------------- tools/testing/selftests/kselftest-nolibc.h | 93 ++++++++++++++++++ tools/testing/selftests/kselftest-std.h | 151 +++++++++++++++++++++++++++++ tools/testing/selftests/kselftest.h | 149 +++------------------------- 5 files changed, 272 insertions(+), 211 deletions(-) --- base-commit: e8d018dd0257f744ca50a729e3d042cf2ec9da65 change-id: 20230405-kselftest-nolibc-cb2ce0446d09 Best regards, -- Mark Brown <broonie@xxxxxxxxxx>