Documentation: kconfig: add recommended way to describe compiler support

It would be nice if the source code is written in the same style.
This proposes the convention for describing the compiler capability
in Kconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This commit is contained in:
Masahiro Yamada 2018-05-28 18:22:08 +09:00
parent caa91ba53e
commit 8373b7d9d1
1 changed files with 18 additions and 0 deletions

View File

@ -473,6 +473,24 @@ config option to 'y' no matter the dependencies.
The dependencies are moved to the symbol GENERIC_IOMAP and we avoid the
situation where select forces a symbol equals to 'y'.
Adding features that need compiler support
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
There are several features that need compiler support. The recommended way
to describe the dependency on the compiler feature is to use "depends on"
followed by a test macro.
config CC_STACKPROTECTOR
bool "Stack Protector buffer overflow detection"
depends on $(cc-option,-fstack-protector)
...
If you need to expose a compiler capability to makefiles and/or C source files,
CC_HAS_ is the recommended prefix for the config option.
config CC_HAS_STACKPROTECTOR_NONE
def_bool $(cc-option,-fno-stack-protector)
Build as module only
~~~~~~~~~~~~~~~~~~~~
To restrict a component build to module-only, qualify its config symbol