Bug#182574: libc6: The pow() function gives incorrect results on special cases (nan, inf...)
On Tue, Mar 11, 2003 at 12:46:20 +0900, GOTO Masanori wrote:
> > The C99 latest public draft has different rules. Perhaps they have
> > changed in the C99 standard, but one has to make sure that this is
> > the case.
>
> Well, even the standard committee, it seems it's difficult to decide
> these special cases.
Yes, the problems are mainly due to overloading different functions
(in the mathematical point of view) by a single function.
OK, there were changes after the latest public draft. I've been told
in fr.comp.lang.c (<m3el5edz77.fsf@uniton.integrable-solutions.net>):
-- pow(-1, ±inf) returns 1.
-- pow(+1, y) returns 1 for any y, even a NaN.
--
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/> - 100%
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