[R-SIG-Mac] third party installer

[Mick Jordan]

What third party installer is used for the standard Mac OS X build? 
Looking at the following I can't figure out where lzma is coming from. I 
am using MacPorts (on El Cap) which puts lzma in /opt/local/include.

Mick Jordan

$ head /Library/Frameworks/R.framework/Resources/etc/Makeconf
# etc/Makeconf.  Generated from Makeconf.in by configure.
#
# ${R_HOME}/etc/Makeconf
#
# R was configured using the following call
# (not including env. vars and site configuration)
# configure  'CC=clang' 'CXX=clang++' 'OBJC=clang' 'F77=gfortran-4.8' 'FC=gfortran-4.8' 'CFLAGS=-Wall -mtune=core2 -g -O2' 'CXXFLAGS=-Wall -mtune=core2 -g -O2' 'OBJCFLAGS=-Wall -mtune=core2 -g -O2' 'FCFLAGS=-Wall -g -O2' 'F77FLAGS=-Wall -g -O2' '--with-system-zlib' '--enable-memory-profiling' 'CPPFLAGS=-I/usr/local/include -I/usr/local/include/freetype2 -I/opt/X11/include' '--x-libraries=/opt/X11/lib' '--x-includes=/usr/local/include' '--enable-R-framework'