[Bug libstdc++/100017] [11/12 regression] error: 'fenv_t' has not been declared in '::' -- canadian compilation fails

[unlvsur at live dot com]

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

--- Comment #65 from cqwrteur <unlvsur at live dot com> ---
(In reply to Jonathan Wakely from comment #62)
> But that's off topic for GCC's bugzilla, please try to focus.

Is that because
#if _GLIBCXX_HAVE_FENV_H
# include <fenv.h>
#endif
here _GLIBCXX_HAVE_FENV_H in the libstdc++ build scripts fails to detect
fenv.h?
What about replacing it with #if __has_include(<fenv.h>) ?

(In reply to Alexander von Gluck from comment #64)
> (In reply to cqwrteur from comment #61)
> > TBH, I failed to see how cross-compile in llvm is simple compared to GCC.
> 
> I mean... bootstrap.  Compiling Canadian toolchains to compile non-Canadian
> toolchains is a pretty difficult task.   It's a big reason the BSD's went
> clang.
> 
> *ANYWAY* wasn't looking to start a holy war.. just point out that Canadian
> builds in gcc are important and should likely have a few base tests.
> 
> (In reply to Jonathan Wakely from comment #62)
> > But that's off topic for GCC's bugzilla, please try to focus.
> 
> Indeed.   Back on topic, the patchset listed definitely does solve the issue
> for us.   I didn't commit it to our gcc fork (that we plan on working to
> upstream for Haiku support) though since a final iteration wasn't decided /
> committed yet here.

Difficult? hmmm. Even middle school kids could easily do this.
I guess nowadays people just randomly search things on the internet for wrong
sources and rely on the things like cross-ng that adds difficulties to it. In
fact cross-ng just makes simple things hard not simple.
I am against all these auto build scripts. They just make simple things hard
and constantly break for all sorts of reasons.