Re: [PATCH 5/5] scripts/gdb: refactor rules for symlink creation

From: Kieran Bingham
Date: Wed Feb 27 2019 - 06:55:50 EST


Hi Yamada-san,

On 19/02/2019 09:33, Masahiro Yamada wrote:
> gdb-scripts is not a real object, but (ab)used like a phony target.
>
> Rewrite the code in a more Kbuild-ish way. Add symlinks to extra-y
> and use if_changed.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> ---
>
> scripts/gdb/linux/Makefile | 18 +++++++++++-------
> 1 file changed, 11 insertions(+), 7 deletions(-)
>
> diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile
> index 7545806..3df395a 100644
> --- a/scripts/gdb/linux/Makefile
> +++ b/scripts/gdb/linux/Makefile
> @@ -1,13 +1,17 @@
> # SPDX-License-Identifier: GPL-2.0
> -always := gdb-scripts
>
> -SRCTREE := $(abspath $(srctree))
> -
> -$(obj)/gdb-scripts:
> ifneq ($(KBUILD_SRC),)
> - $(Q)ln -fsn $(SRCTREE)/$(obj)/*.py $(objtree)/$(obj)
> +
> +symlinks := $(patsubst $(srctree)/$(src)/%,%,$(wildcard $(srctree)/$(src)/*.py))
> +
> +quiet_cmd_symlink = SYMLINK $@
> + cmd_symlink = ln -fsn $(patsubst $(obj)/%,$(abspath $(srctree))/$(src)/%,$@) $@
> +
> +extra-y += $(symlinks)
> +$(addprefix $(obj)/, $(symlinks)): FORCE
> + $(call if_changed,symlink)
> +
> endif
> - @:
>
> quiet_cmd_gen_constants_py = GEN $@
> cmd_gen_constants_py = \
> @@ -18,4 +22,4 @@ extra-y += constants.py
> $(obj)/constants.py: $(src)/constants.py.in FORCE
> $(call if_changed_dep,gen_constants_py)
>
> -clean-files := *.pyc *.pyo $(if $(KBUILD_SRC),*.py)
> +clean-files := *.pyc *.pyo

Perhaps this answers my earlier question.
I guess the extra-y hook is somehow handling the clean up of these files?

Aha - yes, I've just found it in

Documentation/kbuild/makefiles.txt:
> === 5 Kbuild clean infrastructure
> ...
> Kbuild knows targets listed in $(hostprogs-y), $(hostprogs-m), $(always), $(extra-y) and $(targets). They are all deleted during "make clean".

Perfect, so this is much better.

Reviewed-by: Kieran Bingham <kieran.bingham@xxxxxxxxxxxxxxxx>

--
Regards
--
Kieran