On Tue, Jul 6, 2021 at 2:06 AM Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx> wrote: > > > On Sun, Jul 4, 2021 at 7:03 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote: > > > > > > On Fri, Jul 2, 2021 at 12:29 PM Lecopzer Chen > > > <lecopzer.chen@xxxxxxxxxxxx> wrote: > > > > > > > > To check the GNU make version. Used by the LTO Kconfig. > > > > > > > > LTO with MODVERSIONS will fail in generating correct CRC because > > > > the makefile rule doesn't work for make with version 3.8X.[1] > > > > > > > > Thus we need to check make version during selecting on LTO Kconfig. > > > > Add CONFIG_MAKE_VERSION which means MAKE_VERSION in canonical digits > > > > for arithmetic comparisons. > > > > > > > > [1] https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@xxxxxxxxxxxx/ > > > > Signed-off-by: Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx> > > > > --- > > > > > > > > > NACK. > > > > > > "Let's add MAKE_VERSION >= 40200 restriction > > > just because I cannot write correct code that > > > works for older Make" is a horrible idea. > > > > > > Also, Kconfig is supposed to check the compiler > > > (or toolchains) capability, not host tool versions. > > > > I feel like requiring a Make that's half a decade old for a feature > > that also requires a toolchain released last October ago isn't > > entirely unreasonable. > > > > That being said, if Masahiro prefers not to rely on the wildcard > > function's behavior here, which is a reasonable request, we could > > simply use the shell to test for the file's existence: > > > > diff --git a/scripts/Makefile.build b/scripts/Makefile.build > > index 34d257653fb4..c6bd62f518ff 100644 > > --- a/scripts/Makefile.build > > +++ b/scripts/Makefile.build > > @@ -388,7 +388,7 @@ ifeq ($(CONFIG_LTO_CLANG) $(CONFIG_MODVERSIONS),y y) > > cmd_update_lto_symversions = \ > > rm -f $@.symversions \ > > $(foreach n, $(filter-out FORCE,$^), \ > > - $(if $(wildcard $(n).symversions), \ > > + $(if $(shell test -s $(n).symversions && echo y), \ > > ; cat $(n).symversions >> $@.symversions)) > > else > > cmd_update_lto_symversions = echo >/dev/null > > > > This is not quite as efficient as using wildcard, but should work with > > older Make versions too. Thoughts? > > > > > I've tested this in both make-4.3 and 3.81, and the CRC is correct. > But I'm not sure if anyone would have the "arg list too long" issue. > > Tested-by: Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx> Thank you for testing. This should produce a command identical to the wildcard version (with newer Make versions), so that shouldn't be an issue. If nobody objects to this approach, would you mind putting this into a proper patch and sending it as v4? Sami
