Log Message:
-----------
Update pow() tests to check for both errno==EDOM _and_ result==Nan, and
document why this happens. Remove exp() errno check because not needed.
Modified Files:
--------------
pgsql/src/backend/utils/adt:
float.c (r1.138 -> r1.139)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/float.c.diff?r1=1.138&r2=1.139)