x86/build: correctly record dependencies of asm-offsets.s

Going through an intermediate *.new file requires telling the compiler
what the real target is, so that the inclusion of the resulting .*.d
file will actually be useful.

Fixes: 7d2d7a43d014 ("x86/build: limit rebuilding of asm-offsets.h")
Reported-by: Julien Grall <julien@xen.org>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>

diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 7769bb40d741050380b214ddf0e627f4934a4c63..3a9b7e7b2e7211fa9905e0770b437e588027a2a9 100644 (file)
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -241,7 +241,7 @@ efi/buildid.o efi/relocs-dummy.o: $(BASEDIR)/arch/x86/efi/built_in.o
 efi/buildid.o efi/relocs-dummy.o: ;
 
 asm-offsets.s: $(TARGET_SUBARCH)/asm-offsets.c $(BASEDIR)/include/asm-x86/asm-macros.h
-       $(CC) $(filter-out -Wa$(comma)% -flto,$(c_flags)) -S -g0 -o $@.new $<
+       $(CC) $(filter-out -Wa$(comma)% -flto,$(c_flags)) -S -g0 -o $@.new -MQ $@ $<
        $(call move-if-changed,$@.new,$@)
 
 asm-macros.i: CFLAGS-y += -D__ASSEMBLY__ -P