Re: [PATCH v3] kbuild: add debug level and macro defs options

From: Dmitrii Bundin
Date: Thu Aug 18 2022 - 14:57:20 EST


On Thu, Aug 18, 2022 at 7:14 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> -g1 is only possible via DEBUG_INFO_LEVEL, but
> presumably it is not your main interest
> (and not sure if there is anybody interested)
> because the main motivation for your v1
> is to generate macro debug data.

I tested the build process with -g1 and it turned out to generate an
image that is 20% lesser in size.
This is indeed not really my use-case, but are you sure it might not
be helpful in general?

The reason to add DEBUG_INFO_LEVEL was also motivated by the
GCC11+/Clang12+ behavior of -gsplit-dwarf to provide an orthogonal
debug level config.
"The later -g<level> wins" behavior in turns works identically for
both older and newer compiler versions so such an implementation
provides version independent build behavior.
Testing on gcc-11, -gdwarf-<level>/-gdwarf still implies -g2.
It seemed a clearer way to me to explicitly set a debug level that
just wins instead of relying on implicits.

Regards
Dmitrii