Dne 14.6.2017 v 09:08 Cao jin napsal(a): > > > 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 $(MAKEFLAGS) while it has "--debug=jobs", that > make sense to me. Thanks very much, Yamada-san. Well, it more than three years ago. But yes, I believe that was the intention: make --foo=s x$(MAKEFLAGS) => x --foo=s $(firstword x$(MAKEFLAGS)) => x Michal -- 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