rust-lang/rust — pull request #18917 by michaelwoerister (2014-11-13 09:38:15+00:00)
Title: Add --print-sysroot commandline option to rustc

This is in support of the coming "rust-mode" debugger startup scripts.
The implementation given here will print the sysroot if no input filename is given to rustc. Otherwise the option is silently ignored. Let me know if you'd like to have a different behavior.

cc @brson @alexcrichton