libstdc++/7680: float functions undefined in math.h/cmath with #define _XOPEN_SOURCE

[ljrittle@gcc.gnu.org]

Synopsis: float functions undefined in math.h/cmath with #define _XOPEN_SOURCE

State-Changed-From-To: analyzed->closed
State-Changed-By: ljrittle
State-Changed-When: Tue Apr 15 07:33:57 2003
State-Changed-Why:
    Patch on mainline (will be in 3.4).  Not a regression from any 3.0 release.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7680