2018-02-13 17:35 GMT+09:00 Arnd Bergmann <arnd@xxxxxxxx>: > On Tue, Feb 13, 2018 at 2:53 AM, Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: >> On 02/12/2018 05:41 PM, Masahiro Yamada wrote: >>> 2018-02-13 8:48 GMT+09:00 Randy Dunlap <rdunlap@xxxxxxxxxxxxx>: >>>> On 02/12/2018 07:24 AM, Kees Cook wrote: >>>>> On Mon, Feb 12, 2018 at 6:39 AM, Masahiro Yamada >>>>> <yamada.masahiro@xxxxxxxxxxxxx> wrote: >>>> >>>>>>> (And in thinking about this, does Kconfig know the true $CC in use? >>>>>>> i.e. the configured cross compiler, etc?) >>>>>> >>>>>> I was thinking of removing CONFIG_CROSS_COMPILE. >>>>>> >>>>>> A user can dynamically change CROSS_COMPILE from >>>>>> "make menuconfig". >>>>> >>>>> Most builds I've seen implement cross compilers as an environment >>>>> variable during all "make" invocations. >>>> >>>> I agree. I think you would break a bunch of build bots if you remove that. >>> >>> >>> For clarification, I suggested to remove CONFIG_CROSS_COMPILE. >>> >>> The following code: >>> https://github.com/torvalds/linux/blob/v4.16-rc1/Makefile#L315 >>> https://github.com/torvalds/linux/blob/v4.16-rc1/init/Kconfig#L58 >>> >>> I hope build bots are not using this. >>> >>> >>> Passing CROSS_COMPILE via the command line, environment >>> is still supported. >> >> OK, I misunderstood. That one can go away IMO. > > Removing it will break the workflow for some people in a minor way > though. Could we have the top-level Makefile try to detect the > CROSS_COMPILE? Instead of just using CC=gcc as the default, > we could check for ${ARCH}!=`uname -m` and then see if $PATH > contains a ${ARCH}-linux-gcc, ${ARCH}-elf-gcc or ${ARCH}-gcc. > > it will need slightly more complexity to deal with architectures > that have different identifiers in linux and gcc, but I think it would > be a nice feature anyway. > > Arnd Some architectures such as m68k, mips, etc. do this in their arch/*/Makefile by using $(call cc-cross-prefix, ...) But, currently we do not do this globally. It would be possible to do it, but it does not mean backward-compatible with CONFIG_CROSS_COMPILE. -- 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
