Mk/Uses/waf.mk currently adds python 2.7 as a build requirement with 'python_ARGS=2,build'. This is causing deprecation warnings when building ports that use waf:
/!\ aubio-0.4.6: Makefile warnings, please consider fixing /!\
USES=python:2 is deprecated, use USES=python:2.7
Change to 'python_ARGS=2.7,build' to keep waf builds from stalling.