[PATCH] Document powl and tgammal kludges

The following patch documents the remaining kludges that
theraven_at_ committed in r255294 on 2013-09-06.  I have
cleaned up all of the others, but powl and tgammal remain. 
ngie_at_ seems to have documented the existence of powl with
r290605, but did not document the rather poor numerical
accuracy of the result.  tgammal remains undocumented.  As it
is unlikely that theraven_at_ will document the nature of his
kludge nor the existence of tgammal,  I have have prepared
a patch that documents the expected numerical accuracy in BUGS
sections, and have also documented tgammal.


Index: msun/man/exp.3
===================================================================
--- msun/man/exp.3	(revision 2046)
+++ msun/man/exp.3	(working copy)
_at__at_ -28,7 +28,7 _at__at_
 .\"     from: _at_(#)exp.3	6.12 (Berkeley) 7/31/91
 .\" $FreeBSD: head/lib/msun/man/exp.3 290606 2015-11-09 10:41:27Z ngie $
 .\"
-.Dd November 9, 2015
+.Dd December 8, 2017
 .Dt EXP 3
 .Os
 .Sh NAME
_at__at_ -180,6 +180,15 _at__at_
 then \*(Na**0 = 1 too because x**0 = 1 for all finite
 and infinite x, i.e., independently of x.
 .El
+.Sh BUGS
+To conform with newer C/C++ standards, a stub implementation for
+.Nm powl
+was committed to the math library, where
+.Nm powl
+is mapped to
+.Nm pow .
+Thus, the numerical accuracy is at most that of the 53-bit double
+precision implementation.
 .Sh SEE ALSO
 .Xr fenv 3 ,
 .Xr ldexp 3 ,
Index: msun/man/lgamma.3
===================================================================
--- msun/man/lgamma.3	(revision 2046)
+++ msun/man/lgamma.3	(working copy)
_at__at_ -28,7 +28,7 _at__at_
 .\"     from: _at_(#)lgamma.3	6.6 (Berkeley) 12/3/92
 .\" $FreeBSD: head/lib/msun/man/lgamma.3 282015 2015-04-26 11:35:07Z bapt $
 .\"
-.Dd September 12, 2014
+.Dd December 8, 2017
 .Dt LGAMMA 3
 .Os
 .Sh NAME
_at__at_ -43,7 +43,8 _at__at_
 .Nm gammaf ,
 .Nm gammaf_r ,
 .Nm tgamma ,
-.Nm tgammaf
+.Nm tgammaf ,
+.Nm tgammal ,
 .Nd log gamma functions, gamma function
 .Sh LIBRARY
 .Lb libm
_at__at_ -76,6 +77,8 _at__at_
 .Fn tgamma "double x"
 .Ft float
 .Fn tgammaf "float x"
+.Ft "long double"
+.Fn tgammal "long double x"
 .Sh DESCRIPTION
 .Fn lgamma x ,
 .Fn lgammaf x ,
_at__at_ -106,9 +109,10 _at__at_
 but the caller must provide an integer to store the sign of \(*G(x).
 .Pp
 The
-.Fn tgamma x
+.Fn tgamma x ,
+.Fn tgammaf x ,
 and
-.Fn tgammaf x
+.Fn tgammal x
 functions return \(*G(x), with no effect on
 .Fa signgam .
 .Pp
_at__at_ -166,6 +170,15 _at__at_
 For large non-integer negative values,
 .Fn tgamma
 will underflow.
+.Sh BUGS
+To conform with newer C/C++ standards, a stub implementation for
+.Nm tgammal
+was committed to the math library, where
+.Nm tgammal
+is mapped to
+.Nm tgammal .
+Thus, the numerical accuracy is at most that of the 53-bit double
+precision implementation.
 .Sh SEE ALSO
 .Xr math 3
 .Sh STANDARDS
_at__at_ -174,8 +187,9 _at__at_
 .Fn lgammaf ,
 .Fn lgammal ,
 .Fn tgamma ,
+.Fn tgammaf ,
 and
-.Fn tgammaf
+.Fn tgammal
 functions are expected to conform to
 .St -isoC-99 .
 .Sh HISTORY


-- 
Steve