Revert "tools: generic.mk: re-generate object files if flags.txt file…

…s have changed"

This reverts commit 93473c4.

tools/scripts/generic.mk

@@ -301,41 +301,32 @@ LSCRIPT_FLAG = -T$(LSCRIPT)
 endif
 
 define generate_cflags_func
-echo $(subst \",\\\",$(1)) >> $(CFLAGS_FILE).tmp
+echo $(subst \",\\\",$(1)) >> $(CFLAGS_FILE)
 endef
 
 define generate_cppflags_func
-echo $(subst \",\\\",$(1)) >> $(CPPFLAGS_FILE).tmp
+echo $(subst \",\\\",$(1)) >> $(CPPFLAGS_FILE)
 endef
 
 define generate_asflags_func
-echo $(subst \",\\\",$(1)) >> $(ASFLAGS_FILE).tmp
+echo $(subst \",\\\",$(1)) >> $(ASFLAGS_FILE)
 endef
 
 define generate_objs_func
-echo $(1) >> $(OBJS_FILE).tmp
-endef
-
-define overwrite_file_if_different
-	diff $(1) $(2) &> /dev/null || mv -f $(1) $(2)
-endef
-
-define generate_flags_file
-	echo -n > $(1).tmp
-	$(call process_items_in_chunks,$(2),10,$(3))
-	$(call overwrite_file_if_different,$(1).tmp,$(1))
-	rm -f $(1).tmp
+echo $(1) >> $(OBJS_FILE)
 endef
 
 PHONY += pre_build
 pre_build:
 	$(call print,Generating build flags)
-	$(call generate_flags_file,$(CFLAGS_FILE),$(CFLAGS),generate_cflags_func)
-	$(call generate_flags_file,$(CPPFLAGS_FILE),$(CPPFLAGS),generate_cppflags_func)
-	$(call generate_flags_file,$(ASFLAGS_FILE),$(ASFLAGS),generate_asflags_func)
-	$(call generate_flags_file,$(OBJS_FILE),$(OBJS),generate_objs_func)
-
-$(OBJS): $(CFLAGS_FILE) $(CPPFLAGS_FILE) $(ASFLAGS_FILE) $(OBJS_FILE)
+	echo -n > $(CFLAGS_FILE)
+	$(call process_items_in_chunks,$(CFLAGS),10,generate_cflags_func)
+	echo -n > $(CPPFLAGS_FILE)
+	$(call process_items_in_chunks,$(CPPFLAGS),10,generate_cppflags_func)
+	echo -n > $(ASFLAGS_FILE)
+	$(call process_items_in_chunks,$(ASFLAGS),10,generate_asflags_func)
+	echo -n > $(OBJS_FILE)
+	$(call process_items_in_chunks,$(sort $(OBJS)),10,generate_objs_func)
 
 $(BINARY): $(LIB_TARGETS) $(OBJS) $(ASM_OBJS) $(LSCRIPT) $(BOOTOBJ)
 	$(call print,[LD] $(notdir $(OBJS)))