On 24.08.2021 12:50, Anthony PERARD wrote: > This macro does compare command line like if_changed, but it also > rewrite the dependencies generated by $(CC) in order to depend on a > CONFIG_* as generated by kconfig instead of depending on autoconf.h. > This allow to make a change in kconfig options and only rebuild the > object that uses that CONFIG_* option. > > cmd_and_record isn't needed anymore as it is replace by > cmd_and_fixdep. > > There's only one .*.d dependency file left which is explicitly > included as a workound, all the other are been absorb into the .*.cmd > dependency files via `fixdep`. So including .*.d can be removed from > the makefile. > > This imports fixdep.c and if_changed_deps macro from Linux v5.12. > > Signed-off-by: Anthony PERARD <anthony.per...@citrix.com>
Reviewed-by: Jan Beulich <jbeul...@suse.com> with a question: > --- a/xen/Makefile > +++ b/xen/Makefile > @@ -187,6 +187,13 @@ endif > export root-make-done := y > endif # root-make-done > > +# =========================================================================== > +# Rules shared between *config targets and build targets > + > +PHONY += tools_fixdep > +tools_fixdep: > + $(MAKE) -C tools fixdep > + > # Shorthand for kconfig > kconfig = -f $(BASEDIR)/tools/kconfig/Makefile.kconfig ARCH=$(ARCH) > SRCARCH=$(SRCARCH) HOSTCC="$(HOSTCC)" HOSTCXX="$(HOSTCXX)" > > @@ -400,7 +407,7 @@ $(TARGET).gz: $(TARGET) > gzip -n -f -9 < $< > $@.new > mv $@.new $@ > > -$(TARGET): FORCE > +$(TARGET): tools_fixdep FORCE > $(MAKE) -C tools Shouldn't this include building fixdep, in which case the extra dependency here is unnecessary? I can see that it's needed ... > @@ -457,13 +464,13 @@ cscope: > _MAP: > $(NM) -n $(TARGET)-syms | grep -v '\(compiled\)\|\(\.o$$\)\|\( [aUw] > \)\|\(\.\.ng$$\)\|\(LASH[RL]DI\)' > System.map > > -%.o %.i %.s: %.c FORCE > +%.o %.i %.s: %.c tools_fixdep FORCE > $(MAKE) $(build)=$(*D) $(*D)/$(@F) ... in cases like this one. Jan
