I installed using the “curl | sudo sh” method and my first invocation fails.
rpixley@victory> rustc --version
rustc: error while loading shared libraries: librustc_driver-7d23ff90.so: cannot open shared object file: No such file or directory
rpixley@victory> uname -a
Linux victory 3.10.0-229.7.2.el7.x86_64 #1 SMP Fri May 15 21:38:46 EDT 2015 x86_64 x86_64 x86_64 GNU/Linux
rpixley@victory> cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.1 (Maipo)
Not sure where bugs should be filed, but it looks like the library hasn’t been properly installed.