Bug#48695: libc6-dev: log2 function missing in math.h

[Tomasz Motylewski <motyl@stan.chemie.unibas.ch>]

Package: libc6-dev
Version: 2.1.2-7
Severity: normal

Declaration of log2 function is missing from /usr/include/math.h
This breaks compilation of xmgr-4.1.2. configure reports log2 function
as present because it checks it in libm by linking - :
nm /usr/lib/libm.a | grep log2
s_log2.o:
00000000 T __log2
00000000 W log2

This fucntion is present in /usr/include/tgmath.h but including this file
is quite catastrophic.

-- System Information
Debian Release: potato
Kernel Version: Linux crds.chemie.unibas.ch 2.2.13 #1 SMP Fri Oct 29 00:32:37 CEST 1999 i586 unknown

Versions of the packages libc6-dev depends on:
ii  libc6           2.1.2-7        GNU C Library: Shared libraries and timezone