When you build targets that require the kernel configuration, dot-config
is set to 1, then the top-level Makefile includes auto.conf. However,
Make considers its inclusion is optional because the '-include' directive
is used here.
If a necessary configuration file is missing for the external module
building, the following error message is displayed:
ERROR: Kernel configuration is invalid.
include/generated/autoconf.h or include/config/auto.conf are missing.
Run 'make oldconfig && make prepare' on kernel src to fix it.
However, Make still continues building; /bin/false let the creation of
'include/config/auto.config' fail, but Make can ignore the error since
it is included by the '-include' directive.
I guess the reason of using '-include' directive was to suppress
the warning when you build the kernel from a pristine source tree:
Makefile:605: include/config/auto.conf: No such file or directory
The previous commit made sure include/config/auto.conf exists after
the 'make *config' stage. Now, we can use the 'include' directive
without showing the warning.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
endif # KBUILD_EXTMOD
ifeq ($(dot-config),1)
--include include/config/auto.conf
+include include/config/auto.conf
endif
# The all: target is the default when no target is given on the