[Bug libstdc++/100017] error: 'fenv_t' has not been declared in '::' x86_64-w64-mingw32 host cross toolchain fails to build

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100017

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I can only fix the case where the target <fenv.h> (in the build tree) is found
first and then its #include_next finds the host <fenv.h> (installed on the
host).

But that seems to be the case that's breaking the canadian cross build.