Yes. In that particular case loop iterates through en_US (from buildroot), en_US and en_GB.
Of cause, that list can be patched but I don't know if that's correct.
It's look a bit strange if user passes locale which actually absent.

Waldemar, what you think about it?

I made several tests with different locales (en_US, en_GB, ru_RU, C.UTF-8 and C).
The generated header is the same for all the above locale except pure C.

Comment in the same makefile tells about problem with some locales.
I think it would be better to use C locale for fallback.

I attached the tested patch to modify fallback behavior based on Arnout draft.
I also changed the order of calls to raise priority of C.UTF-8 locale.

On Thu, Aug 10, 2017 at 12:36 PM, Arnout Vandecappelle <arnout@mind.be> wrote:


On 10-08-17 11:09, Eugene Yudin wrote:
> The system library makefile handles option the following way
> (extra/locale/Makefile.in):
>  $(locale_OUT)/wctables.h: $(locale_OUT)/gen_wctype
>          @$(disp_gen)
>          $(Q)for locale in $(call qstrip,$(UCLIBC_BUILD_MINIMAL_LOCALES)) en_US
> en_GB; do \
>                   $< $(FLAG-locale-verbose) $$locale > $@ || \
>                  $< $(FLAG-locale-verbose) $$locale.UTF-8 > $@ || \
>                  $< $(FLAG-locale-verbose) $$locale.iso8859-1 > $@ && break; \
>          done
>
> The program "gen_wctype" receives locale name as command line parameter.
> That application call the function setlocale() inside it.
> Some time ago that call was disabled to workaround bug with locales.
> That's the reason for the absence of problems in the past.
> Changes in the last release return this call.

 So the problem really is that this command tries a number of locales, but not
any of the locales actually present on the system?

 I would propose to:
- replace the "en_US en_GB" with "C C.UTF-8" since the latter is much more
likely to be present on the host;
- use '$(sort $(patsubst %.utf8,%,$(shell locale -a)))' as an ultimate fallback.

 Does that sound reasonable? I didn't look at the history if this particular
piece of code, I guess it must have gone through several detours already...

 Regards,
 Arnout

--
Arnout Vandecappelle                          arnout at mind be
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--
Best regards,
Eugene