nolibc's WIFSIGNALED() is true for status 0, so a child that exits with 0 looks as if it was killed by signal 0. I ran into it in a nolibc init for a QEMU test, which reported every clean exit of a child that way.
Patch 1 fixes the macro. Patch 2 adds nolibc-test cases for the wait status macros, which would have caught it. Tested on top of nolibc/for-next f2212892b6a0: - x86_64: without patch 1, the new wifsignaled_exit0 test fails, and the rest of nolibc-test gives the same results with and without it. - x86_64, i386, and arm and sparc64 under qemu-user: all new tests pass. - libc-test against glibc: all new tests pass, so the expected values match glibc. Danish Khateeb (2): tools/nolibc: fix WIFSIGNALED() for status 0 selftests/nolibc: add tests for the wait status macros tools/include/nolibc/types.h | 2 +- tools/testing/selftests/nolibc/nolibc-test.c | 8 ++++++++ 2 files changed, 9 insertions(+), 1 deletion(-) base-commit: f2212892b6a0c2adab438783e9fa8093c90786d7 -- 2.55.0
