It looks like fpsetmask() was deprecated since many years, and that fedisableexcept() is available since FreeBSD 5.3. Since we try to support FreeBSD 9, it's fine to drop support of FreeBSD < 5.3.

I'm concerned by the "CAVEATS" section below. Should we put "#pragma STDC FENV_ACCESS ON" in all .c file using a C double?

@skrah: I saw this pragma in Modules/_decimal/libmpdec/mpdecimal.c. Any idea if applying this patch is fine?

Maybe we can start by applying it to the default branch?

If this patch is required to support arm64, I think that it's ok to apply it to 2.7, 3.4 and 3.5 since we still accept changes to fix platform compatibility issues.

http://www.unix.com/man-page/freebsd/3/fpsetmask/
---
DESCRIPTION
     The routines described herein are deprecated.  New code should use the functionality provided by fenv(3).
---

http://www.unix.com/man-page/freebsd/3/fenv/
---
HISTORY
     The <fenv.h> header first appeared in FreeBSD 5.3.  It supersedes the non-standard routines defined in <ieeefp.h> and documented in fpgetround(3).

CAVEATS
     The FENV_ACCESS pragma can be enabled with
	   #pragma STDC FENV_ACCESS ON
---