cargo: Error running cargo build, "failed to join search paths together"

I’m trying to do my first Cargo build and I’m getting an error:

$ cargo build
failed to join search paths together: path segment contains separator `:`
Does $DYLD_LIBRARY_PATH have an unterminated quote character?

$ echo $DYLD_LIBRARY_PATH


$ rustc --version
rustc 0.13.0-nightly (34d680009 2014-12-22 00:12:47 +0000)

$ cargo --version
cargo 0.0.1-pre-nightly (e11c317 2014-12-21 20:43:45 +0000)

My $DYLD_LIBRARY_PATH appears to be empty, is that causing the problem? What’s supposed to be in that env var? This is a fairly fresh install of OS X, but I do have XCode installed.