[Buildroot] [PATCH] core/help: fix custom help without a .config

[Arnout Vandecappelle <arnout@mind.be>]

On 03/20/16 22:24, Yann E. MORIN wrote:
> When there is no .config, we do not source $(BR2_EXTERNAL)/external.mk.
> So we can not expose the custom help in that situation.
>
> It is now known whether sourcing $(BR2_EXTERNAL)/external.mk outside the
> HAVE_DOT_CONFIG conditional block is entirely safe. Even if it would
> work today, we would have a hard time not breaking it in the future,
> because we do not have automatic checks for that and would need to rely
> on users reporting issues after the fact.
>
> Instead, we require the custom help to be defined in its own file in the
> br2-external tree. This way, we can safely include it unconditionally.

  IMHO that custom help was a bad idea. It's adding complexity, an extra file in 
BR2_EXTERNAL, and really not that useful...

>
> Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> ---
>   Makefile                             | 11 +++++++----
>   docs/manual/customize-outside-br.txt |  7 ++++---
>   2 files changed, 11 insertions(+), 7 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index ea8b1e4..03657d5 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -976,10 +976,13 @@ endif
>   	@echo 'it on-line at http://buildroot.org/docs.html'
>   	@echo
>
> -# This rule does nothing, it is expected to be overloaded by
> -# a br2-external tree or a local.mk . However, it must exist,
> -# as we reference it in the main help, above. Making the rule
> -# .PHONY does not work.
> +ifneq ($(wildcard $(BR2_EXTERNAL)/help.mk),)
> +include $(BR2_EXTERNAL)/help.mk

  Why not just -include?

  Regards,
  Arnout

> +endif
> +
> +# This rule does nothing, it is expected to be overloaded by a
> +# br2-external tree. However, it must exist, as we reference it
> +# as a dependency of the main help, above.
>   help-custom:
>
>   list-defconfigs:
> diff --git a/docs/manual/customize-outside-br.txt b/docs/manual/customize-outside-br.txt
> index be1827e..4f1c752 100644
> --- a/docs/manual/customize-outside-br.txt
> +++ b/docs/manual/customize-outside-br.txt
> @@ -108,9 +108,10 @@ And then in +$(BR2_EXTERNAL)/package/package1+ and
>      normal +make <name>_defconfig+ command. They will be visible under the
>      +User-provided configs+' label in the 'make list-defconfigs' output.
>
> -Additionally, an +external.mk+ file may define the +help-custom+ make
> -rule, to document custom make targets specific to this +BR2_EXTERNAL+
> -tree. The help is completely free-form.
> +Additionally, a +BR2_EXTERNAL+ tree may provide a file named +help.mk+
> +that defines the +help-custom+ make rule, to document custom make
> +targets specific to this +BR2_EXTERNAL+ tree. The help is completely
> +free-form. See below for a sample +$(BR2_EXTERNAL)/help.mk+ file:
>
>   ------
>   help-custom:
>


-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF