New libtool does not work with ccache

[michael johnson]

Hi,
	The new USE_LIBTOOL_VER=15 does not work with devel/ccache.
I have been looking to try and see what the problem could be but I am 
unable to find one.

Here is an example of what happens when a port is compiled using ccache 
when it also uses USE_LIBTOOL_VER=15

/bin/sh /usr/local/bin/libtool15 --mode=link 
/usr/local/libexec/ccache/cc  -O -pipe -march=athlon-xp -Wall 
-Wmissing-prototypes  -L/usr/local/lib -o test-ve-config  
test-ve-config.o -Wl,--export-dynamic -L/usr/local/lib -L/usr/X11R6/lib 
-lgnomeui-2 -lSM -lICE -lbonoboui-2 -lgnomecanvas-2 -lgnome-2 -lpopt 
-lart_lgpl_2 -lpangoft2-1.0 -lbonobo-2 -lgconf-2 -lgnomevfs-2 
-lbonobo-activation -lORBit-2 -lgthread-2.0 -lpthread -lglade-2.0 
-lgtk-x11-2.0 -lxml2 -lgdk-x11-2.0 -lXrandr -lXi -lXinerama -lXcursor 
-latk-1.0 -lgdk_pixbuf-2.0 -lm -lpangoxft-1.0 -lXft -lfreetype -lz 
-lXrender -lXext -lfontconfig -lpangox-1.0 -lX11 -lpango-1.0 
-lgobject-2.0 -lgmodule-2.0 -lglib-2.0 -liconv                       
-lintl                                   -L../vicious-extensions        
  -lvicious
libtool15: link: unable to infer tagged configuration
libtool15: link: specify a tag with `--tag'
gmake[3]: *** [test-ve-config] Error 1
gmake[3]: Leaving directory 
`/usr/ports/x11/gdm2/work/gdm-2.6.0.4/vicious-extensions'

This is true for most all the gnome ports and many many others.

This does not happen with USE_INC_LIBTOOL_VER=ANYVER or 
USE_LIBTOOL_VER=13 so I believe it is something we're doing different 
with libtool?

Cheers,
Michael