On 06/14/2017 09:15 AM, Masahiro Yamada wrote: > 2017-06-13 18:52 GMT+09:00 Cao jin <caoj.fnst@xxxxxxxxxxxxxx>: >> Yamada-san, >> >> I have a question on the current top level Makefile. There are >> following lines, I have trouble to understand "firstword x$(MAKEFLAGS)" >> in 2nd line, why there is a 'x' there? >> >> >> ifneq ($(filter 4.%,$(MAKE_VERSION)),) # make-4 >> ifneq ($(filter %s ,$(firstword x$(MAKEFLAGS))),) > > > I do not understand the 'x' either. > > Michal suggested the code according to the following: > https://patchwork.kernel.org/patch/3291301/ > (I hope Michal can help you.) > It does helps. > > My first guess was, it was added just in case $(MAKEFLAGS) is empty. > Actually $(firstword ) seems to work with empty argument, though. > I see, I guess you are saying it was added in case there is no single-letter flags in $(MAKEFLAGS) while it has "--debug=jobs", that make sense to me. Thanks very much, Yamada-san. -- Sincerely, Cao jin -- 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