Trying to build master and the build process is failing trying to process tinyxml and yaml, such as this:

2>------ Build started: Project: tinyxml, Configuration: Debug x64 ------
2> Building Custom Rule D:/paul/src/OpenColorIO/CMakeLists.txt
2> CMake does not need to re-run because D:\paul\src\OpenColorIO\build\CMakeFiles\generate.stamp is up-to-date.
2> Creating directories for 'tinyxml'
2> Performing download step (verify and extract) for 'tinyxml'
2> -- verifying file...
2> file='D:/paul/src/OpenColorIO/ext/tinyxml_2_6_1.tar.gz'
2>CUSTOMBUILD : -- verifying file... warning : did not verify file - no URL_HASH specified?
2> -- extracting...
2> src='D:/paul/src/OpenColorIO/ext/tinyxml_2_6_1.tar.gz'
2> dst='D:/paul/src/OpenColorIO/build/tinyxml-prefix/src/tinyxml'
2> -- extracting... [tar xfz]
2> -- extracting... [analysis]
2> -- extracting... [rename]
2> -- extracting... [clean up]
2> -- extracting... done
2> No update step for 'tinyxml'
2> Performing patch step for 'tinyxml'
2> 'patch' is not recognized as an internal or external command,
2> operable program or batch file.
2>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V110\Microsoft.CppCommon.targets(172,5): error MSB6006: "cmd.exe" exited with code 9009.
========== Build: 1 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

This later prevents the OpenColorIO target from building.
I also tried with the frederikaalund:master pull request with the same results.

Any suggestions?