> ./configure
checking for a BSD-compatible install... /usr/bin/install -c
checking build system type... i386-apple-darwin15.0.0
checking host system type... i386-apple-darwin15.0.0
checking target system type... i386-apple-darwin15.0.0
checking which SDK to use... configure: error: darwin15.0.0 is not a supported system
On OS X 10.11 Public Beta 1 (15A25h):
Might need to update the m4 script, just like what was done for Yosemite.