lib/53234: Several C99 long double functions missing from math library

[bruce.lilly%gmail.com@localhost]

>Number:         53234
>Category:       lib
>Synopsis:       Several C99 long double functions missing from math library
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    lib-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Apr 30 03:10:00 +0000 2018
>Originator:     Bruce Lilly
>Release:        7.1.2
>Organization:
none
>Environment:
NetBSD z400a.blilly.net 7.1.2_PATCH NetBSD 7.1.2_PATCH (GENERIC) #0: Sun Apr  1 02:21:19 EDT 2018  root%e2500sa.blilly.net@localhost:/usr/obj/sys/arch/amd64/compile/GENERIC amd64 x86_64 Intel 686-class NetBSD
>Description:
Verified on i386 and amd64 ports.

The math lib is missing many long double C99 functions.
This is not intended to be an exhaustive list, but documents those found to be missing while attempting to build ksh93.

# ls -l /usr/lib/libm.a /lib/libm.so.0.*                                                                                                                         
-r--r--r--   1 root     wheel     174260 Mar 15 14:12 /lib/libm.so.0.11                                                                                                                                                       
-r--r--r--   1 root     wheel     432856 Mar 15 14:12 /usr/lib/libm.a

# nm /lib/libm.so.0.11 /usr/lib/libm.a | egrep "erfl|erfcl|expm1l|lgamma1|logpl|log2l|remainderl|tgammal|nexttowardl"      
#

nexttowardl (unless I'm misreading C99) could be implemented by calling nextafterl.
>How-To-Repeat:
See description.
>Fix:
See description for nexttowardl.
Others require implementation of the respective functions.