joyent/node — pull request #8538 by orangemocha (2014-10-10 13:21:50+00:00)
Title: build: vcbuild fix "The input line is too long."

vcbuild.bat is calling vcvars.bat, which doesn't detect if the environment
has already been set. This causes repeated entries to be added to the PATH,
which after a few invocations will lead to an error:
The input line is too long.