Re: [PATCH v1] kbuild: fix sub directory output build of kselftests

[Shuah Khan]

On 6/27/22 1:02 AM, Muhammad Usama Anjum wrote:
> Build of kselftests fail if kernel's top most Makefile is used for
> running or building kselftests with separate output directory which is
> sub-directory. srctree is set to .. erroneously.
>
> make kselftest-all O=/linux_mainline/build
> Makefile:1080: ../scripts/Makefile.extrawarn: No such file or directory
>
> make kselftest-all O=build
> Makefile:1080: ../scripts/Makefile.extrawarn: No such file or directory
>
> Fix this by comparing abs_srctree with CURDIR instead of abs_objtree.
> CURDIR changes based on from where the command has been run and it sets
> the srctree correctly.
>
> Fixes: 25b146c5b8cee("kbuild: allow Kbuild to start from any directory")
> Signed-off-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
> ---
> Changes in V2:
> - Correct the bugfix instead of workaround
>
> V1: https://lore.kernel.org/lkml/20220223191016.1658728-1-usama.anjum@xxxxxxxxxxxxx/
> ---
>   Makefile | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index e66358b64ede..4090d7afcda4 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -238,12 +238,12 @@ ifeq ($(need-sub-make),)
>   # so that IDEs/editors are able to understand relative filenames.
>   MAKEFLAGS += --no-print-directory
>   
> -ifeq ($(abs_srctree),$(abs_objtree))
> +ifeq ($(abs_srctree),$(CURDIR))
>           # building in the source tree
>           srctree := .
>   	building_out_of_srctree :=
>   else
> -        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
> +        ifeq ($(abs_srctree)/,$(dir $(CURDIR)))
>                   # building in a subdirectory of the source tree
>                   srctree := ..
>           else

Please resend cc'ing linux-kselftest

thanks,
-- Shuah