[Bug libstdc++/100017] [11/12 regression] error: 'fenv_t' has not been declared in '::' -- cross toolchain fails to build

[abrodkin at synopsys dot com]

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

--- Comment #25 from Alexey Brodkin <abrodkin at synopsys dot com> ---
> (In reply to Jonathan Wakely from comment #22)
> > *** Bug 101060 has been marked as a duplicate of this bug. ***
> 
> We can fix it today XDXD 
> 
> PROFIT PROFIT PROFIT!!!

Given there's a solution/patch suggested by Yujie Yang is there a chance to get
it fixed in upstream sources?

For the record I'm also seeing initially reported problem when trying to build
canadian cross GCC with Crosstool-NG (well, it's clear build system doesn't
matter but just in case).