Re: [PATCH] kbuild: suppress warnings for single builds of vmlinux.lds, *.a, etc.
From: Masahiro Yamada
Date: Mon Sep 26 2022 - 02:36:33 EST
On Mon, Sep 26, 2022 at 10:27 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> vmlinux-deps is unneeded because the dependency can directly list
> $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
>
> Do not cancel the rule; building an individual vmlinux.lds, built-in.a,
> or lib.a is working now, but the warning "overriding recipe for target"
> is shown.
>
> Without this patch:
>
> $ make arch/x86/kernel/vmlinux.lds
> Makefile:1798: warning: overriding recipe for target 'arch/x86/kernel/vmlinux.lds'
> Makefile:1162: warning: ignoring old recipe for target 'arch/x86/kernel/vmlinux.lds'
> [ snip ]
> LDS arch/x86/kernel/vmlinux.lds
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
I take this back.
After testing this, I noticed vmlinux was not correctly rebuilt.
>
> Makefile | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 244c07f1cc70..3e6974b4ebf2 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1118,7 +1118,8 @@ endif
> export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
> export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
>
> -vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
> +# The actual objects are generated when descending.
> +$(sort $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)): .
>
> # Recurse until adjust_autoksyms.sh is satisfied
> PHONY += autoksyms_recursive
> @@ -1157,10 +1158,6 @@ vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE
>
> targets := vmlinux
>
> -# The actual objects are generated when descending,
> -# make sure no implicit rule kicks in
> -$(sort $(vmlinux-deps)): . ;
> -
> filechk_kernel.release = \
> echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
>
> --
> 2.34.1
>
--
Best Regards
Masahiro Yamada