kbuild: Follow-up to "Reject unexpected values for LLVM="

[PATCH 2/2] tools/build: Reject unexpected values for LLVM=

Posted by Thomas Weißschuh 1 month, 1 week ago

Since commit 502678b88cb3 ("kbuild: Reject unexpected values for LLVM=")
the regular kbuild rejects unexpected values of LLVM=1 instead of
silently treating them as LLVM=1.

Align the tools build to kbuild.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>

---
There is no formal maintainer for this file.
IMO this change should go through kbuild.
---
 tools/scripts/Makefile.include | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
index b5ecf137febc..41971a68972d 100644
--- a/tools/scripts/Makefile.include
+++ b/tools/scripts/Makefile.include
@@ -56,6 +56,8 @@ ifneq ($(filter %/,$(LLVM)),)
 LLVM_PREFIX := $(LLVM)
 else ifneq ($(filter -%,$(LLVM)),)
 LLVM_SUFFIX := $(LLVM)
+else ifneq ($(LLVM),1)
+$(error Invalid value for LLVM, see Documentation/kbuild/llvm.rst)
 endif
 
 $(call allow-override,CC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX))

-- 
2.53.0

Re: [PATCH 2/2] tools/build: Reject unexpected values for LLVM=

Posted by Nathan Chancellor 1 month, 1 week ago

On Thu, Feb 26, 2026 at 10:23:58PM +0100, Thomas Weißschuh wrote:
> Since commit 502678b88cb3 ("kbuild: Reject unexpected values for LLVM=")
> the regular kbuild rejects unexpected values of LLVM=1 instead of
> silently treating them as LLVM=1.
> 
> Align the tools build to kbuild.
> 
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> 
> ---
> There is no formal maintainer for this file.
> IMO this change should go through kbuild.

Ironically I just rejected a tools/ patch going through Kbuild:

  https://lore.kernel.org/20260225192505.GC2755225@ax162/

but since there is no formal maintainer, it is the same change done in
Kbuild, and the risk of fallout is much less than that change, I think
we can make an exception and take it.

Reviewed-by: Nathan Chancellor <nathan@kernel.org>

> ---
>  tools/scripts/Makefile.include | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
> index b5ecf137febc..41971a68972d 100644
> --- a/tools/scripts/Makefile.include
> +++ b/tools/scripts/Makefile.include
> @@ -56,6 +56,8 @@ ifneq ($(filter %/,$(LLVM)),)
>  LLVM_PREFIX := $(LLVM)
>  else ifneq ($(filter -%,$(LLVM)),)
>  LLVM_SUFFIX := $(LLVM)
> +else ifneq ($(LLVM),1)
> +$(error Invalid value for LLVM, see Documentation/kbuild/llvm.rst)
>  endif
>  
>  $(call allow-override,CC,$(LLVM_PREFIX)clang$(LLVM_SUFFIX))
> 
> -- 
> 2.53.0
>

Re: [PATCH 2/2] tools/build: Reject unexpected values for LLVM=

Posted by Nicolas Schier 1 month, 1 week ago

On Thu, Feb 26, 2026 at 02:45:58PM -0700, Nathan Chancellor wrote:
> On Thu, Feb 26, 2026 at 10:23:58PM +0100, Thomas Weißschuh wrote:
> > Since commit 502678b88cb3 ("kbuild: Reject unexpected values for LLVM=")
> > the regular kbuild rejects unexpected values of LLVM=1 instead of
> > silently treating them as LLVM=1.
> > 
> > Align the tools build to kbuild.
> > 
> > Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> > 
> > ---
> > There is no formal maintainer for this file.
> > IMO this change should go through kbuild.
> 
> Ironically I just rejected a tools/ patch going through Kbuild:
> 
>   https://lore.kernel.org/20260225192505.GC2755225@ax162/
> 
> but since there is no formal maintainer, it is the same change done in
> Kbuild, and the risk of fallout is much less than that change, I think
> we can make an exception and take it.

+1

> Reviewed-by: Nathan Chancellor <nathan@kernel.org>

Reviewed-by: Nicolas Schier <nsc@kernel.org>

-- 
Nicolas