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Re: Minimum floating-point requirements
- From: "Joseph S. Myers" <joseph at codesourcery dot com>
- To: Rich Felker <dalias at aerifal dot cx>
- Cc: Steve Munroe <sjmunroe at us dot ibm dot com>, Adhemerval Zanella <azanella at linux dot vnet dot ibm dot com>, David Edelsohn <dje dot gcc at gmail dot com>, <libc-alpha at sourceware dot org>
- Date: Mon, 17 Feb 2014 22:37:21 +0000
- Subject: Re: Minimum floating-point requirements
- Authentication-results: sourceware.org; auth=none
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On Mon, 17 Feb 2014, Rich Felker wrote:
> Anyone doing interval arithmetic wants to change rounding modes.
> However, the need for correct rounding semantics is independent of
> rounding mode. You want it even in default rounding mode.
To be clear: I'm not proposing to make this arithmetic correctly rounding
or support interval arithmetic, simply (given -mieee) make it produce
results in all rounding modes that are actually valid long double values
at all (and in the case of overflow or underflow, are consistent with the
rounding mode).
--
Joseph S. Myers
joseph@codesourcery.com