[Bug middle-end/108300] `abort()` macro cause bootstrap failure on *-w64-mingw32

[lh_mouse at 126 dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108300

--- Comment #8 from LIU Hao <lh_mouse at 126 dot com> ---
The commit above just lets GCC bootstrap on Windows. The cause of this issue is
still there.

Maybe it's possible to replace all direct calls to `abort()` in gcc and libcpp
with `fancy_abort (__FILE__, __LINE__, __FUNCTION__)`, and eventually get rid
of that macro.