Hello Dmitry, On Tue, 11 Mar 2025 19:07:05 +0300, Dmitry Antipov <dmantipov@xxxxxxxxx> wrote: > When using 'make LLVM=1 W=1 -C tools/testing/selftests/pid_namespace' > with clang-20, I've noticed the following: > > pid_max.c:42:8: error: call to undeclared function 'mount'; ISO > C99 and later do not support implicit function declarations > [-Wimplicit-function-declaration] > 42 | ret = mount("", "/", NULL, MS_PRIVATE | MS_REC, 0); > | ^ > pid_max.c:42:29: error: use of undeclared identifier 'MS_PRIVATE' > 42 | ret = mount("", "/", NULL, MS_PRIVATE | MS_REC, 0); > | ^ > ... > > So include '<sys/mount.h>' to add all of the required declarations. > > Signed-off-by: Dmitry Antipov <dmantipov@xxxxxxxxx> > --- > tools/testing/selftests/pid_namespace/pid_max.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/tools/testing/selftests/pid_namespace/pid_max.c b/tools/testing/selftests/pid_namespace/pid_max.c > index 51c414faabb0..972bedc475f1 100644 > --- a/tools/testing/selftests/pid_namespace/pid_max.c > +++ b/tools/testing/selftests/pid_namespace/pid_max.c > @@ -11,6 +11,7 @@ > #include <string.h> > #include <syscall.h> > #include <sys/wait.h> > +#include <sys/mount.h> > > #include "../kselftest_harness.h" > #include "../pidfd/pidfd.h" Predated patches already available, see https://lore.kernel.org/linux-kselftest/20250115105211.390370-1-ps.report@xxxxxxx/ https://lore.kernel.org/linux-kselftest/20250115105211.390370-2-ps.report@xxxxxxx/ https://lore.kernel.org/linux-kselftest/20250115105211.390370-3-ps.report@xxxxxxx/ Regards, Peter