The header file xlocale.h has been removed in glibc 2.26.
Quoting the release notes[1]:
* The nonstandard header <xlocale.h> has been removed. Most programs
should use <locale.h> instead. If you have a specific need for the
definition of locale_t with no other declarations, please contact
libc-alpha@sourceware.org and explain.
I've backported HaxeFoundation/neko@e286c8f330
against version 2.1.0 and the build now succeeds.
Signed-off-by: aszlig <aszlig@nix.build>
