Samba4 master. make install error: Could not install the file libreplace.so

[steve]

samba master around 30 mins ago on our test domain which currently has
Version 4.2.0pre1-GIT-6965f91


[ 127/4134] Linking default/lib/replace/libreplace.so
[ 128/4134] Linking default/lib/replace/libreplace.inst.so
* installing bin/default/lib/replace/libreplace.inst.so
as /usr/local/samba/lib/private/libreplace.so
Waf: Leaving directory `/home/steve/samba-master/bin'
Could not install the file '/usr/local/samba/lib/private/libreplace.so'
make: *** [install] Error 1

Can anyone help me get it installed?
Cheers,
Steve