[PATCH] uml: fix W=1 missing-include-dirs warnings

[Randy Dunlap]

On 4/15/21 12:04 AM, Masahiro Yamada wrote:
> On Thu, Apr 15, 2021 at 4:02 PM Randy Dunlap <rdunlap at infradead.org> wrote:
>>
>> On 4/14/21 11:52 PM, Masahiro Yamada wrote:
>>> On Thu, Apr 15, 2021 at 4:27 AM Randy Dunlap <rdunlap at infradead.org> wrote:
>>>>
>>>> Currently when using "W=1" with UML builds, there are over 700 warnings
>>>> like so:
>>>>
>>>>   CC      arch/um/drivers/stderr_console.o
>>>> cc1: warning: ./arch/um/include/uapi: No such file or directory [-Wmissing-include-dirs]
>>>>
>>>> but arch/um/ does not have include/uapi/ at all, so don't
>>>> include arch/um/include/uapi/ in USERINCLUDE for UML.
>>
>>
>>>> Option 4: simply mkdir arch/um/include/uapi
>>>>         That's what I did first, just as a test, and it works.
>>>
>>>
>>> I like Option 4.
>>>
>>> But, you cannot do "mkdir -p arch/um/include/uapi" at build-time
>>> because the build system should not touch the source tree(, which
>>> might be read-only)
>>> for O= building.
>>>
>>> How about adding
>>>
>>>   arch/um/include/uapi/asm/Kbuild,
>>>
>>> which is just having a SPDX one-liner?
>>
>> Wow!  :)
>> That's what Al Viro suggested also.
>> I'll submit that patch later today (Thursday my time).
>>
>> thanks.
>> --
>> ~Randy
>>
> 
> 
> BTW, after fixing this UML problem,
> can we move -Wmissing-include-dirs to the top Makefile?

I don't see why not. And eventually remove this one:

fs/btrfs/Makefile:subdir-ccflags-y += -Wmissing-include-dirs

> Is there any other source of -Wmissing-include-dirs
> warnings?

I can't give a full answer on that; only that I haven't
seen any others and also that all other arch/*/include/
do have a uapi/ subdir.

-- 
~Randy