Building BridgeSuport on Mojave continues to fail

MojaveBridgeSupportBuildFails.log

linking shared-object bridgesupportparser.bundle
+ /bin/mkdir -p -m 0755 /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3
+ /usr/bin/rsync -rlpt bridgesupportparser.bundle /Users/michaelp/RubySpielwiese/BridgeSupport/SYMROOT
+ /usr/bin/rsync -rlpt bridgesupportparser.bundle /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3
+ /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/strip -x /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3/bridgesupportparser.bundle
+ /usr/bin/rsync -rlpt bridgesupportparser.rb /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3
/usr/bin/touch /Users/michaelp/RubySpielwiese/BridgeSupport/OBJROOT/.BS_RUBY.made
/usr/bin/install -m 0755 -o root -g wheel -d /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/include
/usr/bin/install -m 0444      -o root      -g wheel /Users/michaelp/RubySpielwiese/BridgeSupport/include/_BS_bool.h /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/include
*** Finished Building bridgesupport.bundle: So 30 Sep 2018 13:38:47 CEST
/usr/bin/touch /Users/michaelp/RubySpielwiese/BridgeSupport/OBJROOT/.BS_INCLUDE.made
*** Started Building .bridgesupport files: So 30 Sep 2018 13:38:48 CEST
# TODO : generate BridgeSupport files in each system library frameworks
# DSTROOT='/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT' RUBYLIB='/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3' ruby build.rb
RUBYLIB='/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3' ruby gen_bridge_metadata.rb -c '-I/usr/include/CommonCrypto -I/usr/include/objc' -e exceptions/libSystem.xml -o /Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/libSystem.bridgesupport /usr/include/asl.h /usr/include/notify*.h /usr/include/copyfile.h /usr/include/sandbox.h /usr/include/launch.h /usr/include/CommonCrypto/*.h /usr/include/objc/NSObjCRuntime.h
Received exception: No such file or directory @ realpath_rec - /usr/include:
/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3/bridgesupportparser.rb:967:in `realpath'
/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3/bridgesupportparser.rb:967:in `realpath'
/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3/bridgesupportparser.rb:967:in `block in initialize'
/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3/bridgesupportparser.rb:941:in `each'
/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/ruby-2.3/bridgesupportparser.rb:941:in `initialize'
gen_bridge_metadata.rb:613:in `new'
gen_bridge_metadata.rb:613:in `_parse'
gen_bridge_metadata.rb:805:in `parse'
gen_bridge_metadata.rb:2510:in `block in <main>'
/Users/michaelp/.rbenv/versions/2.3.7/lib/ruby/2.3.0/optparse.rb:1062:in `initialize'
gen_bridge_metadata.rb:2436:in `new'
gen_bridge_metadata.rb:2436:in `<main>'
No such file or directory @ realpath_rec - /usr/include
Usage: gen_bridge_metadata.rb [options] <headers...>
Use the `-h' flag or consult gen_bridge_metadata(1) for help.
make: *** [/Users/michaelp/RubySpielwiese/BridgeSupport/DSTROOT/System/Library/BridgeSupport/libSystem.bridgesupport] Error 1