[PATCH] kbuild: Fix running modpost with musl libc

From: Samuel Holland
Date: Tue Dec 27 2022 - 16:48:47 EST


commit 3d57e1b7b1d4 ("kbuild: refactor the prerequisites of the modpost
rule") moved 'vmlinux.o' inside modpost-args, possibly before some of
the other options. However, getopt() in musl libc follows POSIX and
stops looking for options upon reaching the first non-option argument.
As a result, the '-T' option is misinterpreted as a positional argument,
and the build fails:

make -f ./scripts/Makefile.modpost
scripts/mod/modpost -E -o Module.symvers vmlinux.o -T modules.order
-T: No such file or directory
make[1]: *** [scripts/Makefile.modpost:137: Module.symvers] Error 1
make: *** [Makefile:1960: modpost] Error 2

The fix is to move all options before 'vmlinux.o' in modpost-args.

Fixes: 3d57e1b7b1d4 ("kbuild: refactor the prerequisites of the modpost rule")
Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx>
---

scripts/Makefile.modpost | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
index 5eb5e8280379..0ee296cf520c 100644
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -55,6 +55,17 @@ ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),)
modpost-args += -n
endif

+ifneq ($(KBUILD_MODPOST_WARN)$(missing-input),)
+modpost-args += -w
+endif
+
+# Read out modules.order to pass in modpost.
+# Otherwise, allmodconfig would fail with "Argument list too long".
+ifdef KBUILD_MODULES
+modpost-args += -T $(MODORDER)
+modpost-deps += $(MODORDER)
+endif
+
ifeq ($(KBUILD_EXTMOD),)

# Generate the list of in-tree objects in vmlinux
@@ -113,17 +124,6 @@ modpost-args += -e $(addprefix -i , $(KBUILD_EXTRA_SYMBOLS))

endif # ($(KBUILD_EXTMOD),)

-ifneq ($(KBUILD_MODPOST_WARN)$(missing-input),)
-modpost-args += -w
-endif
-
-ifdef KBUILD_MODULES
-modpost-args += -T $(MODORDER)
-modpost-deps += $(MODORDER)
-endif
-
-# Read out modules.order to pass in modpost.
-# Otherwise, allmodconfig would fail with "Argument list too long".
quiet_cmd_modpost = MODPOST $@
cmd_modpost = \
$(if $(missing-input), \
--
2.37.4