Re: [PATCH 1/3] kbuild: provide a new place to check necessary host tools

From: Sam Ravnborg
Date: Tue Oct 16 2018 - 11:47:26 EST


Hi Masahiro.

Looks good, a few nits below.

Sam

> The top Makefile is too cluttered
So true...

> This adds a new file scripts/Makefile.toolcheck to check additional
> tools depending on the kernel configuration. This check is run
> immediately after syncconfig, i.e., when a user attempts to build
> something with a new set of CONFIG options.
>
> [1] https://patchwork.kernel.org/patch/10516049/
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> ---
The use of toolcheck-y should be documented in Documentation/kbuild/...


>
> Makefile | 1 +
> scripts/Makefile.toolcheck | 35 +++++++++++++++++++++++++++++++++++
> 2 files changed, 36 insertions(+)
> create mode 100644 scripts/Makefile.toolcheck
>
> diff --git a/Makefile b/Makefile
> index bf3786e..23a204a 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -633,6 +633,7 @@ $(KCONFIG_CONFIG) include/config/auto.conf.cmd: ;
> # include/config/auto.conf (which mirrors .config).
> include/config/%.conf: $(KCONFIG_CONFIG) include/config/auto.conf.cmd
> $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
> + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.toolcheck
> else
> # External modules and some install targets need include/generated/autoconf.h
> # and include/config/auto.conf but do not care if they are up-to-date.
> diff --git a/scripts/Makefile.toolcheck b/scripts/Makefile.toolcheck
> new file mode 100644
> index 0000000..f3c165d
> --- /dev/null
> +++ b/scripts/Makefile.toolcheck
> @@ -0,0 +1,35 @@
> +# SPDX-License-Identifier: GPL-2.0
> +# ===========================================================================
> +# Host tools check
> +# ===========================================================================
> +#
> +# Some additional tools might be required depending on the kernel configuration.
> +# Check if they are installed on the host machine, and if missing, error out
> +# with a user-friendly message.
> +
> +include include/config/auto.conf
> +
> +__toolcheck:
> + @:
> +
> +PHONY += $(toolcheck-y)
> +__toolcheck: $(toolcheck-y)
> +
> +define populate_toolcheck
> +__toolcheck: check_$(1)
> +PHONY += check_$(1)
> +check_$(1):
> + $(Q){ $(chk_$(1)); } >/dev/null 2>&1 || { \
> + echo "*" >&2; \
> + for msg in $(msg_$(1)); \
> + do \
> + echo "* $$$${msg}" >&2; \
> + done; \
> + echo "*" >&2; \
> + /bin/false; \
> + }
Very dense, but usign if [ ... ] may result is somethign that
is a little more readable.

And maybe a litle hint on the usage...

> +$(foreach c, $(toolcheck-y), $(eval $(call populate_toolcheck,$(c))))
Good use of $(eval ...)