standards/176031: [msun] pow() returns roots of negative values.

[pfg at FreeBSD.org]

Synopsis: [msun] pow() returns roots of negative values.

State-Changed-From-To: open->closed
State-Changed-By: pfg
State-Changed-When: Tue Feb 12 23:00:25 UTC 2013
State-Changed-Why: 
Invalid: -current correctly returns NaN.

http://www.freebsd.org/cgi/query-pr.cgi?pr=176031