Stranges errors are observed when building U-Boot master for almost any
RISC-V board, the messages are in two types, one is about duplicated
symbols,
u-boot/arch/riscv/cpu//mtrap.S:32: multiple definition of `trap_entry';
arch/riscv/cpu/mtrap.o: u-boot/arch/riscv/cpu//mtrap.S:32: first
defined here
and the other is fixdep's complaint about missing dependency files,
fixdep: error opening file: arch/riscv/cpu/.mtrap.o.d: No such file or
directory
fixdep: error opening file: arch/riscv/cpu//.start.o.d: No such file or
directory
where the latter could only be reproduced when building parallelly.
Both the two types of errors are about files in arch/riscv/cpu, and
there's a suspicious slash character in the reported path. Looking
through RISC-V-specific Makefiles, there's only one place that may
expand to such a path,
libs-y += arch/riscv/cpu/$(CPU)/
The right hand expands to "arch/riscv/cpu//" if $(CPU) isn't defined at
the time of including. With some debug statement added to
arch/riscv/Makefile, the output proves that arch/riscv/Makefile is
included twice, once with $(CPU) undefined and once defined correctly
according to CONFIG_SYS_CPU.
Futher bisecting shows an extra include statement against
arch/$(SRCARCH)/Makefile is added in earlier bump of Kbuild system. But
the statement is evaluated before config.mk is included and definition
of $(CPU), causing objects in arch/riscv/cpu/ are built and linked twice
(once as "arch/riscv/cpu/*", and once as "arch/riscv/cpu//*"), resulting
in the error.
Let's simply remove the extra include to fix these nasty errors. For
config targets, bumping Kbuild also introduced a new include to
arch/$(SRCARCH)/Makefile, which is removed as well for consistency.
Fixes: 5f520875bdf ("kbuild: Bump the build system to 5.1")
Signed-off-by: Yao Zi <zi...@disroot.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
---
Changes from v1
- Don't describe the problem as RISC-V-specific since it may affect ARM
builds as well.
- Prevent config targets from including for architecture-specific
Makefile as well for consistency.
- Add comments to explain the removal.
- Link to v1:
https://lore.kernel.org/u-boot/20250709161418.21287-2-zi...@disroot.org/
Makefile | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/Makefile b/Makefile
index da53efa09f1..e745cc618ba 100644
--- a/Makefile
+++ b/Makefile
@@ -635,8 +635,9 @@ ifeq ($(config-targets),1)
# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
# KBUILD_DEFCONFIG may point out an alternative default configuration
# used for 'make defconfig'
-# Modified for U-Boot
--include arch/$(SRCARCH)/Makefile
+# Modified for U-Boot: we don't include arch/$(SRCARCH)/Makefile for config
+# targets, which is useless since U-Boot has no architecture defining its own
+# KBUILD_{DEF,K}CONFIG, or CROSS_COMPILE.
export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
config: scripts_basic outputmakefile FORCE
@@ -724,8 +725,10 @@ endif
ARCH_CPPFLAGS :=
ARCH_AFLAGS :=
ARCH_CFLAGS :=
-# Modified for U-Boot
--include arch/$(SRCARCH)/Makefile
+# Modified for U-Boot: we put off the include of arch/$(SRCARCH)/Makefile until
+# making sure include/config/auto.conf is up-to-date and include of config.mk,
+# because the architecture-specific Makefile may make use of variables defined
+# in config.mk. See also the comment about autoconf_is_old.
ifeq ($(dot-config),1)
ifeq ($(may-sync-config),1)
--
2.50.0
