kbuild: Figure out flags independently from pass

We now have the information which objects are being built
modular / built-in in Rules.make, so use this information instead
of passing flags to the sub makes.

Makefile

@@ -172,7 +172,7 @@ export	NETWORKS DRIVERS LIBS HEAD LDFLAGS LINKFLAGS MAKEBOOT ASFLAGS
 # ---------------------------------------------------------------------------
 
 boot: vmlinux
-	@$(MAKE) CFLAGS="$(CFLAGS) $(CFLAGS_KERNEL)" AFLAGS="$(AFLAGS) $(AFLAGS_KERNEL)" -C arch/$(ARCH)/boot
+	@$(MAKE) -C arch/$(ARCH)/boot
 
 # Build vmlinux
 # ---------------------------------------------------------------------------
@@ -202,7 +202,7 @@ define rule_link_vmlinux
 	echo Generating build number
 	. scripts/mkversion > .tmpversion
 	mv -f .tmpversion .version
-	$(MAKE) CFLAGS="$(CFLAGS) $(CFLAGS_KERNEL)" AFLAGS="$(AFLAGS) $(AFLAGS_KERNEL)" -C init
+	$(MAKE) -C init
 	echo $(cmd_link_vmlinux)
 	$(cmd_link_vmlinux)
 	echo 'cmd_$@ := $(cmd_link_vmlinux)' > $(@D)/.$(@F).cmd
@@ -212,11 +212,10 @@ endef
 vmlinux: $(CONFIGURATION) $(vmlinux-objs) dummy
 	$(call if_changed_rule,link_vmlinux)
 
-#	The actual objects are generated when descending, make sure
-#	no implicit rule kicks in
+#	The actual objects are generated when descending, 
+#	make sure no implicit rule kicks in
 
-$(sort $(vmlinux-objs)): linuxsubdirs
-	@
+$(sort $(vmlinux-objs)): linuxsubdirs ;
 
 # 	Handle descending into subdirectories listed in $(SUBDIRS)
 
@@ -224,7 +223,7 @@ $(sort $(vmlinux-objs)): linuxsubdirs
 linuxsubdirs: $(patsubst %, _dir_%, $(SUBDIRS))
 
 $(patsubst %, _dir_%, $(SUBDIRS)) : dummy include/linux/version.h include/config/MARKER
-	@$(MAKE) CFLAGS="$(CFLAGS) $(CFLAGS_KERNEL)" AFLAGS="$(AFLAGS) $(AFLAGS_KERNEL)" -C $(patsubst _dir_%, %, $@)
+	@$(MAKE) -C $(patsubst _dir_%, %, $@)
 
 # Configuration
 # ---------------------------------------------------------------------------
@@ -266,8 +265,6 @@ include/linux/version.h: ./Makefile
 	@echo Generating $@
 	@. scripts/mkversion_h $@ $(KERNELRELEASE) $(VERSION) $(PATCHLEVEL) $(SUBLEVEL)
 
-comma	:= ,
-
 # ---------------------------------------------------------------------------
 # Generate dependencies
 
@@ -296,7 +293,7 @@ modules: $(patsubst %, _mod_%, $(SUBDIRS))
 
 .PHONY: $(patsubst %, _mod_%, $(SUBDIRS))
 $(patsubst %, _mod_%, $(SUBDIRS)) : include/linux/version.h include/config/MARKER
-	@$(MAKE) -C $(patsubst _mod_%, %, $@) CFLAGS="$(CFLAGS) $(CFLAGS_MODULE)" AFLAGS="$(AFLAGS) $(AFLAGS_MODULE)" modules
+	@$(MAKE) -C $(patsubst _mod_%, %, $@) modules
 
 #	Install modules
 
@@ -497,7 +494,7 @@ tags: dummy
 # FIXME: anybody still using this?
 
 fs lib mm ipc kernel drivers net sound: dummy
-	$(MAKE) CFLAGS="$(CFLAGS) $(CFLAGS_KERNEL)" AFLAGS="$(AFLAGS) $(AFLAGS_KERNEL)" $(subst $@, _dir_$@, $@)
+	$(MAKE) $(subst $@, _dir_$@, $@)
 
 # Make a backup
 # FIXME anybody still using this?

Rules.make

@@ -2,11 +2,6 @@
 # This file contains rules which are shared between multiple Makefiles.
 #
 
-#
-# False targets.
-#
-.PHONY: dummy
-
 #
 # Special variables which should not be exported
 #
@@ -110,9 +105,21 @@ first_rule: all_targets
 # Compile C sources (.c)
 # ---------------------------------------------------------------------------
 
-$(export-objs): export_flags := $(EXPORT_FLAGS)
+# FIXME: if we don't know if built-in or modular, assume built-in.
+# Only happens in Makefiles which override the default first_rule:
+modkern_cflags := $(CFLAGS_KERNEL)
+
+$(real-objs-y)      : modkern_cflags := $(CFLAGS_KERNEL)
+$(real-objs-y:.o=.i): modkern_cflags := $(CFLAGS_KERNEL)
+$(real-objs-y:.o=.s): modkern_cflags := $(CFLAGS_KERNEL)
+
+$(real-objs-m)      : modkern_cflags := $(CFLAGS_MODULE)
+$(real-objs-m:.o=.i): modkern_cflags := $(CFLAGS_MODULE)
+$(real-objs-m:.o=.s): modkern_cflags := $(CFLAGS_MODULE)
+
+$(export-objs)      : export_flags := $(EXPORT_FLAGS)
 
-c_flags = $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o) -DKBUILD_BASENAME=$(subst $(comma),_,$(subst -,_,$(*F))) $(export_flags)
+c_flags = $(CFLAGS) $(modkern_cflags) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o) -DKBUILD_BASENAME=$(subst $(comma),_,$(subst -,_,$(*F))) $(export_flags)
 
 cmd_cc_s_c = $(CC) $(c_flags) -S $< -o $@
 
@@ -132,7 +139,16 @@ cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 # Compile assembler sources (.S)
 # ---------------------------------------------------------------------------
 
-a_flags = $(AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
+# FIXME (s.a.)
+modkern_aflags := $(AFLAGS_KERNEL)
+
+$(real-objs-y)      : modkern_aflags := $(AFLAGS_KERNEL)
+$(real-objs-y:.o=.s): modkern_aflags := $(AFLAGS_KERNEL)
+
+$(real-objs-m)      : modkern_aflags := $(AFLAGS_MODULE)
+$(real-objs-m:.o=.s): modkern_aflags := $(AFLAGS_MODULE)
+
+a_flags = $(AFLAGS) $(modkern_aflags) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
 
 cmd_as_s_S = $(CPP) $(a_flags) $< > $@
 
@@ -166,7 +182,7 @@ endif
 all_targets: $(O_TARGET) $(L_TARGET) sub_dirs
 
 # To build objects in subdirs, we need to descend into the directories
-$(subdir-obj-y): sub_dirs
+$(sort $(subdir-obj-y)): sub_dirs ;
 
 #
 # Rule to compile a set of .o files into one .o file
@@ -267,13 +283,14 @@ modules_install: _modinst__ \
 	 $(patsubst %,_modinst_%,$(MOD_SUB_DIRS))
 
 #
-# A rule to do nothing
+# FIXME: This is usually called FORCE, to express what it's used for
 #
+.PHONY: dummy
 dummy:
 
 #
 # This is useful for testing
-#
+# FIXME: really?
 script:
 	$(SCRIPT)
 
@@ -363,7 +380,6 @@ endif
 
 endif # CONFIG_MODULES
 
-
 #
 # include dependency files if they exist
 #