Re: [PATCH] gcc-plugins: Disable GCC_PLUGIN_CYC_COMPLEXITY for s390

Heiko Carstens
2021-02-22T13:00:59Z

On Sun, Feb 21, 2021 at 02:56:50PM -0800, Guenter Roeck wrote:
> Commit 334ef6ed06fa ("init/Kconfig: make COMPILE_TEST depend on !S390") disabled
> COMPILE_TEST for s390. At the same time, "make allmodconfig/allyesconfig" for
> s390 is still supported. However, it generates thousands of compiler
> messages such as the following, making it highly impractical to run.
>
> Cyclomatic Complexity 1 scripts/mod/devicetable-offsets.c:main
> Cyclomatic Complexity 1 scripts/mod/devicetable-offsets.c:_GLOBAL__sub_I_00100_0_main
>
> Since GCC_PLUGIN_CYC_COMPLEXITY is primarily used for testing, disable it
> when building s390 images.
>
> Cc: Arnd Bergmann <arnd@kernel.org>
> Cc: Heiko Carstens <hca@linux.ibm.com>
> Fixes: 334ef6ed06fa ("init/Kconfig: make COMPILE_TEST depend on !S390")
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> scripts/gcc-plugins/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
> index ab9eb4cbe33a..5e9bb500f443 100644
> --- a/scripts/gcc-plugins/Kconfig
> +++ b/scripts/gcc-plugins/Kconfig
> @@ -21,7 +21,7 @@ if GCC_PLUGINS
>
> config GCC_PLUGIN_CYC_COMPLEXITY
> bool "Compute the cyclomatic complexity of a function" if EXPERT
> - depends on !COMPILE_TEST # too noisy
> + depends on !COMPILE_TEST && !S390 # too noisy

I don't see a reason to disable this in general for s390. COMPILE_TEST
was only disabled for s390 because a lot of irrelevant configs didn't
compile and it would cause a lot of unnecessary work to fix that.

However the !COMPILE_TEST dependency here looks more like it was
misused in lack of a possibility to detect if the config was generated
with allyesconfig/allmodconfig. Maybe that could be added somehow to
Kconfig?