Support clang with attributes
Support clang with attributes

Kitware/sprokit,Kitware/sprokit,Kitware/sprokit,linus-sherrill/sprokit,mathstuf/sprokit,linus-sherrill/sprokit,linus-sherrill/sprokit,Kitware/sprokit,linus-sherrill/sprokit,mathstuf/sprokit,mathstuf/sprokit,mathstuf/sprokit