Some source files here are converted by code7bit. code7bit: https://github.com/katahiromz/code7bit code7bit makes the string literals 8-bit clean. If source contains any non-8-bit-clean strings, non-Latin developer cannot build the project on MSVC. 8-bit clean https://en.wikipedia.org/wiki/8-bit_clean To edit a file converted by code7bit, you have to revert it at first. To revert, please execute code7bit -r . After edit, to convert again, please execute code7bit -c .