28f94a4429
Kbuild descends into a directory by either 'y' or 'm', but there is an important difference. Kbuild combines the built-in objects into built-in.a in each directory. The built-in.a in the directory visited by obj-y is merged into the built-in.a in the parent directory. This merge happens recursively when Kbuild is ascending back towards the top directory, then built-in objects are linked into vmlinux eventually. This works properly only when the Makefile specifying obj-y is reachable by the chain of obj-y. On the other hand, Kbuild does not take built-in.a from the directory visited by obj-m. This it, all the objects in that directory are supposed to be modular. If Kbuild descends into a directory by obj-m, but the Makefile in the sub-directory specifies obj-y, those objects are just left orphan. The current statement "Kbuild only uses this information to decide that it needs to visit the directory" is misleading. Clarify the difference. Reported-by: Johan Hovold <johan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Johan Hovold <johan@kernel.org> |
||
|---|---|---|
| .. | ||
| Kconfig.recursion-issue-01 | ||
| Kconfig.recursion-issue-02 | ||
| Kconfig.select-break | ||
| headers_install.rst | ||
| index.rst | ||
| issues.rst | ||
| kbuild.rst | ||
| kconfig-language.rst | ||
| kconfig-macro-language.rst | ||
| kconfig.rst | ||
| makefiles.rst | ||
| modules.rst | ||
| reproducible-builds.rst | ||