Reported for MinGW64 in #gfortran:

< NightStrike_> ../../../../../build/gcc/src/libgfortran/io/write.c:394:8: warning: passing argument 2 of 'write_default_char4' discards 'const' qualifier from pointer target type [enabled by default]

That's the line
              write_default_char4 (dtp, crlf, 2, 0);
where
      const gfc_char4_t crlf[] = {0x000d,0x000a};
and
write_default_char4 (st_parameter_dt *dtp, gfc_char4_t *source,
                     int src_len, int w_len)

I wonder whether one shouldn't simply make the second parameter of write_default_char4 "const".