[Bug libc/3479] Incorrect rounding in strtod()

["joseph at codesourcery dot com" <sourceware-bugzilla at sourceware dot org>]

------- Additional Comments From joseph at codesourcery dot com  2007-02-05 16:48 -------
Subject: Re:  Incorrect rounding in strtod()

On Sun, 4 Feb 2007, john at thesalmons dot org wrote:

> The attached code checks this condition.  It's *much* easier to check
> this than to check the more detailed requirement of 7.20.1.3.  As a
> result, the code doesn't actually prove that glibc is in error.  It's
> possible that gcc's handling of literal floats is in error.  

We know GCC's handling of floating-point literals doesn't always get the 
last bit rounded correctly, but showing this requires specially chosen 
examples (that I could only find for IEEE quad long double).  So the cases 
here probably don't result from a GCC bug - but it might still be wise to 
write such tests so that GCC only needs parse a hex float value, so as to 
disentangle the glibc and GCC issues.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21718



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http://sourceware.org/bugzilla/show_bug.cgi?id=3479

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