Re: [PATCH 2/6] kbuild: allow Kbuild to start from any directory

[Masahiro Yamada <yamada.masahiro@socionext.com>]

Hi Kieran,


On Tue, Apr 2, 2019 at 1:41 PM Kieran Bingham <kbingham@kernel.org> wrote:
>
> Hi Yamada-san,
>
> Thank you for the patches,
>
> I like the direction this series is taking.
>
> Small spelling error spotted below...
> But as I've now gone through all of it I'll offer
>
> Reviewed-by: Kieran Bingham <kbingham@kernel.org>
>
>
> On 30/03/2019 12:04, Masahiro Yamada wrote:
> > Kbuild always runs in the top of the output directory.
> >
> > If Make starts in the source directory with O=, it relocates the
> > working directory to the location specified by O=.
> >
> > Also, users can start build from the output directory by using the
> > Makefile generated by scripts/mkmakefile.
> >
> > With a little more effort, Kbuild will be able to start from any
> > directory path.
> >
> > This commit allows to specify the source directory by using
> > the -f option.
> >
> > For example, you can do:
> >
> >   $ cd path/to/output/dir
> >   $ make -f path/to/source/dir/Makefile
> >
> > Or, for the equivalent behavior, you can do:
> >
> >   $ make O=path/to/output/dir -f path/to/source/dir/Makefile
> >
> > KBUILD_SRC is now deprecated.
> >
> > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> > ---
> >
> >  Makefile | 87 +++++++++++++++++++++++++++++++++++++---------------------------
> >  1 file changed, 50 insertions(+), 37 deletions(-)
> >
> > diff --git a/Makefile b/Makefile
> > index 9cbd367..1b2a70e 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -96,56 +96,65 @@ endif
> >
> >  export quiet Q KBUILD_VERBOSE
> >
> > -# kbuild supports saving output files in a separate directory.
> > -# To locate output files in a separate directory two syntaxes are supported.
> > -# In both cases the working directory must be the root of the kernel src.
> > +# Kbuild will save output files in the current working directory.
> > +# This does not need to match to the root of the kernel source tree.
> > +#
> > +# For example, you can do this:
> > +#
> > +#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
> > +#
> > +# If you want to save output files in a different location, there are
> > +# two syntaxes to specify it.
> > +#
> >  # 1) O=
> >  # Use "make O=dir/to/store/output/files/"
> >  #
> >  # 2) Set KBUILD_OUTPUT
> > -# Set the environment variable KBUILD_OUTPUT to point to the directory
> > -# where the output files shall be placed.
> > -# export KBUILD_OUTPUT=dir/to/store/output/files/
> > -# make
> > +# Set the environment variable KBUILD_OUTPUT to point to the output directory.
> > +# export KBUILD_OUTPUT=dir/to/store/output/files/; make
> >  #
> >  # The O= assignment takes precedence over the KBUILD_OUTPUT environment
> >  # variable.
> >
> > -# KBUILD_SRC is not intended to be used by the regular user (for now),
> > -# it is set on invocation of make with KBUILD_OUTPUT or O= specified.
> > -
> > -# OK, Make called in directory where kernel src resides
> > -# Do we want to locate output files in a separate directory?
> > +# Do we want to change the working directory?
> >  ifeq ("$(origin O)", "command line")
> >    KBUILD_OUTPUT := $(O)
> >  endif
> >
> > -ifneq ($(words $(subst :, ,$(CURDIR))), 1)
> > -  $(error main directory cannot contain spaces nor colons)
> > +ifneq ($(KBUILD_OUTPUT),)
> > +# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
> > +# expand a shell special character '~'. We use a bit tredious way to handle it.
>
> very minor, but I noticed while looking through the series ^^
>
> s/bit tredious/somewhat tedious/


Oops, 'tredious' is a typo.

As a non-native, I do not understand the difference
between 'a bit' and 'somewhat', but I will apply it.

Thanks.





-- 
Best Regards
Masahiro Yamada