$ git clone git@github.com:rust-num/num-traits.git
# Check out a known bad commit, just in case.
$ git checkout 8915b74ae4f4fe42fae329852a2e24934c0623d5
$ cargo +nightly doc
thread 'rustc' has overflowed its stack
fatal runtime error: stack overflow
error: Could not document `num-traits`.

Caused by:
  process didn't exit successfully: `rustdoc --crate-name num_traits src/lib.rs --color always -o /Users/benesch/Sites/materialize/num-traits/target/doc --cfg 'feature="default"' --cfg 'feature="std"' -L dependency=/Users/benesch/Sites/materialize/num-traits/target/debug/deps --cfg has_i128` (signal: 6, SIGABRT: process abort signal)