FreeBSD Port: x11/xorg-clients build fails

[Jann Roeder]

Hello,
I tried to build the xorg-clients port in order to install the updated 
xterm port and got this error:

making all in programs/xdriinfo...
rm -f xdriinfo
cc -o xdriinfo -O2 -fno-strict-aliasing -pipe -ansi -pedantic 
-Wno-system-headers -Dasm=__asm   -Wall -Wpointer-arith -Wundef 
-L/usr/ports/x11/xorg-clients/work/xc/exports/lib   xdriinfo.o -lGL 
-lXext -lX11 -L/usr/X11R6/lib -pthread -Wl,-rpath,/usr/X11R6/lib 
-Wl,-rpath-link,/usr/ports/x11/xorg-clients/work/xc/exports/lib
xdriinfo.o(.text+0x4a): In function `main':
: undefined reference to `glXGetProcAddress'
xdriinfo.o(.text+0x5b): In function `main':
: undefined reference to `glXGetProcAddress'
*** Error code 1

Stop in /usr/ports/x11/xorg-clients/work/xc/programs/xdriinfo.
*** Error code 1

Stop in /usr/ports/x11/xorg-clients/work/xc/programs.
*** Error code 1

Stop in /usr/ports/x11/xorg-clients.

Jann Röder