public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug libstdc++/84949] -ffast-math bugged with respect to NaNs
[not found] <bug-84949-4@http.gcc.gnu.org/bugzilla/>
@ 2020-09-18 7:09 ` kretz at kde dot org
2021-09-21 6:41 ` rguenth at gcc dot gnu.org
2023-10-10 13:58 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 3+ messages in thread
From: kretz at kde dot org @ 2020-09-18 7:09 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84949
--- Comment #8 from Matthias Kretz (Vir) <kretz at kde dot org> ---
I've been doing a lot of research into the numeric_limits intent/meaning
recently. I also implemented and used alternative interpretations of "has NaN"
and "is IEC559". My conclusion: std::numeric_limits means "has NaN bitpattern"
and "has IEC559 bit layout" not "has NaNs with NaN behavior" and "has IEC559
behavior". The former are still useful even if the latter don't hold. The C++
standard could be clearer on this matter though.
Thus, it seems the status quo is working as intended. It's just that we're
missing a standard interface to ask for behavior conformance.
Any progress on this issue must go via WG21.
Besides: my patch in #6 was not accepted (ABI concerns: specifically ABI
breakage from using different -f... flags), so should this PR be closed?
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug libstdc++/84949] -ffast-math bugged with respect to NaNs
[not found] <bug-84949-4@http.gcc.gnu.org/bugzilla/>
2020-09-18 7:09 ` [Bug libstdc++/84949] -ffast-math bugged with respect to NaNs kretz at kde dot org
@ 2021-09-21 6:41 ` rguenth at gcc dot gnu.org
2023-10-10 13:58 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2021-09-21 6:41 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84949
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |SUSPENDED
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think this is a good bug to dup to since it contains good information, so
lets suspend it.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug libstdc++/84949] -ffast-math bugged with respect to NaNs
[not found] <bug-84949-4@http.gcc.gnu.org/bugzilla/>
2020-09-18 7:09 ` [Bug libstdc++/84949] -ffast-math bugged with respect to NaNs kretz at kde dot org
2021-09-21 6:41 ` rguenth at gcc dot gnu.org
@ 2023-10-10 13:58 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-10-10 13:58 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84949
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |Zahira.Ammarguellat at intel dot c
| |om
--- Comment #10 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 111759 has been marked as a duplicate of this bug. ***
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-10-10 13:58 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
[not found] <bug-84949-4@http.gcc.gnu.org/bugzilla/>
2020-09-18 7:09 ` [Bug libstdc++/84949] -ffast-math bugged with respect to NaNs kretz at kde dot org
2021-09-21 6:41 ` rguenth at gcc dot gnu.org
2023-10-10 13:58 ` pinskia at gcc dot gnu.org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).