Only run libc-test on nightly
Only run libc-test on nightly

Otherwise just make sure the library builds on other Rust versions

cybergeek94/libc,diwic/libc,zethra/libc,rust-lang-nursery/libc,cactorium/libc,DiamondLovesYou/libc,philippkeller/libc,rust-lang/libc,rust-lang/libc,anatol/libc,rust-lang-nursery/libc,diwic/libc,cactorium/libc,superriva/libc,cybergeek94/libc,mneumann/libc,zethra/libc,cactorium/libc,anatol/libc,philippkeller/libc,zethra/libc,superriva/libc,cybergeek94/libc,philippkeller/libc,superriva/libc,rust-lang-nursery/libc,mneumann/libc,DiamondLovesYou/libc,DiamondLovesYou/libc,DiamondLovesYou/libc,anatol/libc,diwic/libc,diwic/libc,mneumann/libc,rust-lang/libc