[PATCH v5 1/4] kbuild: respect skip_gendwarfksyms in cmd_gensymtypes_S

[Giuliano Procida <gprocida@google.com>]

Commit 9c3681f9b9fd ("kbuild: Add gendwarfksyms as an alternative to
genksyms") added `skip_gendwarfksyms` handling to `cmd_gensymtypes_c` so
that `rust/exports.o` could skip symbol version generation, as CRCs are
computed directly from the defining Rust and helper object files.

`cmd_gensymtypes_S` is meant to mirror `cmd_gensymtypes_c`, as noted in
the comments above both definitions, but omitted the
`skip_gendwarfksyms` check. Respect `skip_gendwarfksyms` in
`cmd_gensymtypes_S` as well so that `rust/exports.c` can be converted to
assembly without `getasmexports` attempting to compile undeclared Rust
and helper symbols against `<asm/asm-prototypes.h>` when
`CONFIG_MODVERSIONS` is enabled.

Signed-off-by: Giuliano Procida <gprocida@google.com>
---
 scripts/Makefile.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 6127feb970c6..873a9ed62a18 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -428,11 +428,11 @@ getasmexports =								\
      $(call getexportsymbols,EXPORT_SYMBOL(\1);) ; }
 
 ifdef CONFIG_GENDWARFKSYMS
-cmd_gensymtypes_S =							\
+cmd_gensymtypes_S = $(if $(skip_gendwarfksyms),,			\
 	$(getasmexports) |						\
 	$(CC) $(c_flags) -c -o $(@:.o=.gendwarfksyms.o) -xc -;		\
 	$(call getexportsymbols,\1) |					\
-	$(gendwarfksyms) $(@:.o=.gendwarfksyms.o)
+	$(gendwarfksyms) $(@:.o=.gendwarfksyms.o))
 else
 cmd_gensymtypes_S =							\
 	$(getasmexports) |						\
-- 
2.56.0.567.gdb80ae8cd5-goog