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From: Florian Weimer <fweimer@redhat.com>
To: Rich Felker <dalias@libc.org>
Cc: John M <johnm@braincalibration.de>,  musl@lists.openwall.com
References: <ZZKBretdrHqBM1Ph@alberich> <20240101134309.GN1427497@port70.net>
	<20240101174752.GL4163@brightrain.aerifal.cx>
Date: Tue, 02 Jan 2024 11:16:15 +0100
In-Reply-To: <20240101174752.GL4163@brightrain.aerifal.cx> (Rich Felker's
	message of "Mon, 1 Jan 2024 12:47:53 -0500")
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Subject: Re: [musl] Wrong rounding in printf when precision is not set to max

* Rich Felker:

> Note that, even then, there are lots of gotchas. The x87's "single"
> and "double" modes are not actually IEEE single and double, but
> nonstandard types with the IEEE significand precision but excess
> exponent range that's truncated via double-rounding whenever the
> intermediate is spilled to memory.

Doesn't setting the control word avoid double rounding?

Thanks,
Florian