kbuild: move .vmlinux.objs rule to Makefile.modpost

.vmlinux.objs is used by modpost, so scripts/Makefile.modpost is
a better place to generate it.

It is used only when CONFIG_MODVERSIONS=y. It should be guarded
by "ifdef CONFIG_MODVERSIONS".

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

Author: masahir0y

Makefile

@@ -1477,7 +1477,7 @@ endif # CONFIG_MODULES
 # Directories & files removed with 'make clean'
 CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
 	       modules.builtin modules.builtin.modinfo modules.nsdeps \
-	       compile_commands.json .thinlto-cache
+	       compile_commands.json .thinlto-cache .vmlinux.objs
 
 # Directories & files removed with 'make mrproper'
 MRPROPER_FILES += include/config include/generated          \

scripts/Makefile.modpost

@@ -57,6 +57,32 @@ vmlinux.symvers: vmlinux.o
 
 __modpost: vmlinux.symvers
 
+# Generate the list of in-tree objects in vmlinux
+# ---------------------------------------------------------------------------
+
+# This is used to retrieve symbol versions generated by genksyms.
+ifdef CONFIG_MODVERSIONS
+vmlinux.symvers: .vmlinux.objs
+endif
+
+# Ignore libgcc.a
+# Some architectures do '$(CC) --print-libgcc-file-name' to borrow libgcc.a
+# from the toolchain, but there is no EXPORT_SYMBOL in it.
+
+quiet_cmd_vmlinux_objs = GEN     $@
+      cmd_vmlinux_objs =		\
+	for f in $(real-prereqs); do	\
+		case $${f} in		\
+		*libgcc.a) ;;		\
+		*.a) $(AR) t $${f} ;;	\
+		*) echo $${f} ;;	\
+		esac			\
+	done > $@
+
+targets += .vmlinux.objs
+.vmlinux.objs: $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE
+	$(call if_changed,vmlinux_objs)
+
 else
 
 ifeq ($(KBUILD_EXTMOD),)
@@ -134,13 +160,13 @@ ifneq ($(KBUILD_MODPOST_NOFINAL),1)
 	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal
 endif
 
+endif
+
 PHONY += FORCE
 FORCE:
 
 existing-targets := $(wildcard $(sort $(targets)))
 
 -include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
 
-endif
-
 .PHONY: $(PHONY)

scripts/link-vmlinux.sh

@@ -199,7 +199,6 @@ cleanup()
 	rm -f System.map
 	rm -f vmlinux
 	rm -f vmlinux.map
-	rm -f .vmlinux.objs
 	rm -f .vmlinux.export.c
 }
 
@@ -218,23 +217,6 @@ fi
 #link vmlinux.o
 ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o"
 
-# Generate the list of in-tree objects in vmlinux
-#
-# This is used to retrieve symbol versions generated by genksyms.
-for f in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do
-	case ${f} in
-	*libgcc.a)
-		# Some architectures do '$(CC) --print-libgcc-file-name' to
-		# borrow libgcc.a from the toolchain.
-		# There is no EXPORT_SYMBOL in external objects. Ignore this.
-		;;
-	*.a)
-		${AR} t ${f} ;;
-	*)
-		echo ${f} ;;
-	esac
-done > .vmlinux.objs
-
 # modpost vmlinux.o to check for section mismatches
 ${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1