Rust 错误：linking with `cc` failed： exit code： 1

我有single.rs文件.当我以rustc test1.rs编译它时，我得到一个错误:

    error: linking with `cc` failed: exit code: 1
note: cc '-m64' '-L' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib' '-o' 'test1' 'test1.o' '-Wl,-force_load,/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/libmorestack.a' '-Wl,-dead_strip' '-nodefaultlibs' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/libstd-4e7c5e5c.rlib' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/libcollections-4e7c5e5c.rlib' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/libunicode-4e7c5e5c.rlib' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/librand-4e7c5e5c.rlib' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/liballoc-4e7c5e5c.rlib' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/liblibc-4e7c5e5c.rlib' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib/libcore-4e7c5e5c.rlib' '-L' '/usr/local/Cellar/rust/1.0.0-alpha/lib/rustlib/x86_64-apple-darwin/lib' '-L' '/Users/alex/Documents/projects/rust/.rust/lib/x86_64-apple-darwin' '-L' '/Users/alex/Documents/projects/rust/lib/x86_64-apple-darwin' '-lSystem' '-lpthread' '-lc' '-lm' '-lcompiler-rt'
note: ld: warning: directory not found for option '-L/Users/alex/Documents/projects/rust/.rust/lib/x86_64-apple-darwin'
ld: warning: directory not found for option '-L/Users/alex/Documents/projects/rust/lib/x86_64-apple-darwin'
ld: can't open output file for writing: test1, errno=21 for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

error: aborting due to previous error


$ rustc --version
rustc 1.0.0-dev

我看过一些与此相关的话题，但没有一个能帮我解决这个问题.