check if target os filesystem supports case-insensitive or not at build time is not correct

[leleliu008]

In our build script define a macro called CASE_INSENSITIVE_FILENAMES, this macro determined at build time. I think this logical is not correct. because many different filesystems can be used in one os. one filesystem is case-insensitive, another can be case-sensitive, so, this feature only can be determined at runtime.

[masatake]

You are correct. However, I am not positive about implementing it because all file systems (+ OS) I use are case-sensitive. I want to take my time for improving the parsers and writing new parsers instead.

Unless the changes for this issue are not so complicated, I will not reject a pull request for this topic.

I wonder this one is related to this issue. https://github.com/universal-ctags/ctags/issues/1216