Re: [PATCH] selftests: Fix kcmp build to not require headers install

From: Michael Ellerman
Date: Mon Mar 16 2015 - 07:00:59 EST

On Fri, 2015-03-13 at 19:45 -0600, Shuah Khan wrote:
> Change CFLAGS to look in uapi to allow kcmp to be built without
> requiring headers install. This will make it easier to run tests
> without going through the headers install step.
> Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
> ---
> tools/testing/selftests/kcmp/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> diff --git a/tools/testing/selftests/kcmp/Makefile b/tools/testing/selftests/kcmp/Makefile
> index ff0eefd..d405ad4 100644
> --- a/tools/testing/selftests/kcmp/Makefile
> +++ b/tools/testing/selftests/kcmp/Makefile
> @@ -1,5 +1,5 @@
> -CFLAGS += -I../../../../usr/include/
> +CFLAGS += -I../../../../include/uapi -I../../../../usr/include/

Hi Shuah,

Sorry but this is wrong. The contents of include/uapi are not the same as the
exported kernel headers.

Mixing the unprocessed kernel headers with user headers leads to all sorts of
mess, eg:

$ cc -I../../../../include/uapi -I../../../../usr/include/ kcmp_test.c -o kcmp_test
In file included from /usr/include/powerpc64le-linux-gnu/asm/ptrace.h:27:0,
from /usr/include/powerpc64le-linux-gnu/asm/sigcontext.h:11,
from /usr/include/powerpc64le-linux-gnu/bits/sigcontext.h:27,
from /usr/include/signal.h:332,
from kcmp_test.c:5:
../../../../include/uapi/linux/types.h:9:2: warning: #warning "Attempt to use kernel headers from user space, see"; [-Wcpp]
#warning "Attempt to use kernel headers from user space, see";
In file included from ../../../../include/uapi/linux/posix_types.h:4:0,
from ../../../../include/uapi/linux/types.h:13,
from /usr/include/powerpc64le-linux-gnu/asm/ptrace.h:27,
from /usr/include/powerpc64le-linux-gnu/asm/sigcontext.h:11,
from /usr/include/powerpc64le-linux-gnu/bits/sigcontext.h:27,
from /usr/include/signal.h:332,
from kcmp_test.c:5:
../../../../include/uapi/linux/stddef.h:1:28: fatal error: linux/compiler.h: No such file or directory
#include <linux/compiler.h>
compilation terminated.
<builtin>: recipe for target 'kcmp_test' failed
make: *** [kcmp_test] Error 1

If you want to make it easier to build tests that need the kernel headers then
maybe kselftest should depend on headers_install?


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at