2017-10-10 7:04 GMT+09:00 Doug Anderson <dianders@xxxxxxxxxxxx>: > Hi, > > On Tue, Oct 3, 2017 at 8:56 PM, Masahiro Yamada > <yamada.masahiro@xxxxxxxxxxxxx> wrote: >> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include >> index 9ffd3dd..222d0a2 100644 >> --- a/scripts/Kbuild.include >> +++ b/scripts/Kbuild.include >> @@ -96,6 +96,13 @@ try-run = $(shell set -e; \ >> fi; \ >> rm -f "$$TMP" "$$TMPO") >> >> +# hostcc-option >> +# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) >> +hostcc-option = $(call __cc-option, $(HOSTCC),\ >> + $(HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) > > I believe you've got a bug here. You're calling "__cc-option" which > isn't defined if "need-compiler" is not 1, right? Good catch! >> + >> +ifeq ($(need-compiler),1) > > The way this patch works is a bit non-obvious I think. I wonder if > anyone else will be confused like I am... > > Basically if "need-compiler" is not 1 then things like "cc-option" > won't be defined at all. ...but we'll still _call_ them in other > Makefiles. This call of an undefined variable will just evaluate to > an empty string. Thus, for instance: > > CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,) > > ...will just set CFLAGS_KCOV to the empty string if "need-compiler" > isn't 1, right? > > > I guess that's fine, but maybe at least document it somewhere? IMHO > it would be even better if somehow you still defined each of these to > something bogus in an else clause, like: > > as-option = --err_noncompile_target > as-instr = --err_noncompile_target > cc-option = --err_noncompile_target > ... > ... > > The idea being that if someone accidentally invoked the C compiler (or > if there was some other conditional code in the Makefile based on the > result of one of these functions) it would be obvious what was going > on. Make sense. Thanks for your idea! I am still wondering if I should apply this one because your cache approach provides much more benefits. (that is why I prefixed this 4/4 with RFC.) Maybe I will send v2, or maybe not. -- Best Regards Masahiro Yamada -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
