Re: [PATCH] CodingStyle: Expand IS_ENABLED() documentation

From: Paul Bolle
Date: Tue Sep 27 2016 - 15:32:26 EST


On Tue, 2016-09-27 at 14:08 -0500, Bjorn Helgaas wrote:

> --- a/Documentation/CodingStyle
> +++ b/Documentation/CodingStyle

> +Because the compiler processes the block, you have to use an #ifdef instead
> +of IS_ENABLED() when code inside the block references symbols that will not
> +exist if the condition is not met.ÂÂDifferent CONFIG_FOO autoconf.h symbols
> +are generated for modular Kconfig options than for builtin ones, so you
> +need "#if defined(CONFIG_FOO) || defined(CONFIG_FOO_MODULE)"

Isn't that equivalent to "#if IS_ENABLED(CONFIG_FOO)"?

> if FOO can be
> +a module:
> +
> + .config include/generated/autoconf.h
> + ------------ ----------------------------
> + CONFIG_FOO=y #define CONFIG_FOO 1
> + CONFIG_FOO=m #define CONFIG_FOO_MODULE 1


Paul Bolle