@codebrainz sorry I didn't look closely enough at it, saw the first error in your build post was Scintilla and assumed it was all C++17 regex issues, but in fact most of them are ctgas errors:
- missing <fnmatch.h> which is the linux glob file match header, but its in ctags/fnmatch - at least some of the missing macros are defined in ctags/gnu_regex/regex_internal.h, didn't check them all
So it looks like the meson.build needs to declare those two directories as includes so the headers will be found, not sure why it works on Linux, possibly its using the system headers of the same name or finding them because they are in the same directory as the file being compiled.