[Bug c++/100460] [11/12/13 Regression][modules] mingw build broken due to use of unsupported open() flags

[schwab--- via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100460

--- Comment #4 from Andreas Schwab <sch...@linux-m68k.org> ---
They are needed for O_CREAT.