From: "Thomas Weißschuh" <thomas.weissschuh@linutronix.de>
To: Masahiro Yamada <masahiroy@kernel.org>,
Nathan Chancellor <nathan@kernel.org>,
Nicolas Schier <nicolas.schier@linux.dev>,
Nick Desaulniers <nick.desaulniers+lkml@gmail.com>,
Bill Wendling <morbo@google.com>,
Justin Stitt <justinstitt@google.com>
Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org,
llvm@lists.linux.dev, stable@vger.kernel.org,
"Thomas Weißschuh" <thomas.weissschuh@linutronix.de>
Subject: [PATCH] kbuild: userprogs: use correct linker when mixing clang and GNU ld
Date: Thu, 24 Jul 2025 10:32:45 +0200 [thread overview]
Message-ID: <20250724-userprogs-clang-gnu-ld-v1-1-3d3d071e53a7@linutronix.de> (raw)
The userprogs infrastructure does not expect clang being used with GNU ld
and in that case uses /usr/bin/ld for linking, not the configured $(LD).
This fallback is problematic as it will break when cross-compiling.
Mixing clang and GNU ld is used for example when building for SPARC64,
as ld.lld is not sufficient; see Documentation/kbuild/llvm.rst.
Relax the check around --ld-path so it gets used for all linkers.
Fixes: dfc1b168a8c4 ("kbuild: userprogs: use correct lld when linking through clang")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
Nathan, you originally proposed the check for $(CONFIG_LD_IS_LLD) [0],
could you take a look at this?
[0] https://lore.kernel.org/all/20250213175437.GA2756218@ax162/
---
Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Makefile b/Makefile
index c09766beb7eff4780574682b8ea44475fc0a5188..e300c6546c845c300edb5f0033719963c7da8f9b 100644
--- a/Makefile
+++ b/Makefile
@@ -1134,7 +1134,7 @@ KBUILD_USERCFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD
KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
# userspace programs are linked via the compiler, use the correct linker
-ifeq ($(CONFIG_CC_IS_CLANG)$(CONFIG_LD_IS_LLD),yy)
+ifneq ($(CONFIG_CC_IS_CLANG),)
KBUILD_USERLDFLAGS += --ld-path=$(LD)
endif
---
base-commit: 6832a9317eee280117cd695fa885b2b7a7a38daf
change-id: 20250723-userprogs-clang-gnu-ld-7a1c16fc852d
Best regards,
--
Thomas Weißschuh <thomas.weissschuh@linutronix.de>
next reply other threads:[~2025-07-24 8:33 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-24 8:32 Thomas Weißschuh [this message]
2025-07-24 23:10 ` [PATCH] kbuild: userprogs: use correct linker when mixing clang and GNU ld Nathan Chancellor
2025-07-25 10:36 ` Thomas Weißschuh
2025-07-26 10:34 ` Masahiro Yamada
2025-07-30 0:47 ` Nathan Chancellor
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