On 12/10/20 5:10 PM, Andrew Delgadillo wrote:
On Thu, Dec 10, 2020 at 3:08 PM Nick Desaulniers
<ndesaulniers@xxxxxxxxxx> wrote:
On Thu, Dec 3, 2020 at 2:10 PM Andrew Delgadillo <adelg@xxxxxxxxxx> wrote:
lib.mk defaults to gcc when CC is not set. When building selftests
as part of a kernel compilation, MAKEFLAGS is cleared to allow implicit
build rules to be used. This has the side-effect of clearing the CC
variable, which will cause selftests to be built with gcc regardless of
if we are using gcc or clang. To remedy this, propagate the CC variable
when clearing makeflags to ensure the correct compiler is used.
Signed-off-by: Andrew Delgadillo <adelg@xxxxxxxxxx>
Hi Andrew, thanks for the patch. Can you walk me through how to build
the selftests?
Documentation/dev-tools/kselftest.rst says:
$ make -C tools/testing/selftests
And if I do:
$ make CC=clang defconfig
$ make CC=clang -C tools/testing/selftests -j
I observe a spew of errors. If I apply your patch and rerun the
above, I see what looks like the same spew of errors. Am I "holding
it wrong" or could the docs use a refresh?
Hi Nick, sure thing!
I also see a slew of errors when building with make -C
tools/testing/selftests. However, that is not the problem I am trying
to solve. I believe we are seeing errors building that way because it
is missing some make variables that are normally set up when building
from the kernel's top level makefile.
Both options are supported and should work.
make -C tools/testing/selftests
make kselftest
That being said, I use gcc. Can you send the errors you are seeing?
It is possible, a few tests aren't building and need to be fixed
for clang and gcc.
thanks,
-- Shuah
