[R-SIG-Mac] Tcl/Tk Package issue on Leopard

[Bill Northcott]

It seems the Tcl/Tk package included in the current 2.6.2 universal  
package has an issue on 64 bit capable hardware.

The included 64 bit architectures in the Tk binaries are linked  
against the Xorg version of X11 installed in /use/local.  While this  
is necessary for Tiger, it seems unnecessary for Leopard which has 4  
way fat X11 libraries.

To make matters worse, this does not seem to be mentioned on the R for  
MacOS X developers web page or in the read me for the main R installer  
metapackage.  The only place I can find the need for the Xorg  
installation mentioned is in the readme for the tcl/tk package which  
most people won't get to read.

Any attempt to run fat executables which use /usr/local/lib/ 
tk8.4.dylib on a 64 bit capable Mac fail with a baffling error if Xorg  
X11 is not installed.

[pmg5bn:~] billn% /usr/local/bin/wish8.4
dyld: Library not loaded: /usr/local/X11R7/lib/libX11.6.dylib
   Referenced from: /usr/local/lib/libtk8.4.dylib
   Reason: image not found
Trace/BPT trap

this baffled me because
[pmg5bn:~] billn% otool -L /usr/local/lib/libtk8.4.dylib
/usr/local/lib/libtk8.4.dylib:
	/usr/local/lib/libtk8.4.dylib (compatibility version 8.4.0, current  
version 8.4.14)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current  
version 88.3.3)
	/usr/X11R6/lib/libX11.6.dylib (compatibility version 6.2.0, current  
version 6.2.0)
	/usr/lib/libgcc_s.1.dylib (compatibility version 1.0.0, current  
version 1.0.0)

  does not appear to be linked against anything in /usr/local/X11R7


Would it be possible to do different builds for Tiger and Leopard?   
For Tiger, the need for Xorg X11 needs to be documented, while for  
Leopard, it would be better not used.

Thanks
Bill Northcott