On 2017/5/3 14:12, Xi Ruoyao wrote: > Liu Hao (CCed him) once said his (maybe modified) libstdc++ > also support locale name "" (empty string). Maybe he can help > you. No I didn't modify GCC or libstdc++ source. The "" (empty string) locale works fine and conforms to the standard on my computer (that is, it is identical to the "C" locale). -- Best regards, LH_Mouse