`cargo build` fails with parse error on my ~/.gitconfig

[laughinghan]

In a brand new repo that happens to have hyper as a dependency, I get:

$ cargo build
error: failed to load source for a dependency on `hyper`

Caused by:
  Unable to update registry https://github.com/rust-lang/crates.io-index

Caused by:
  [7/-1] failed to parse config file: Invalid configuration key (in /Users/han/.gitconfig:34, column 0)

I just git cloned this repo, so I know my .gitconfig does not have any parse errors, and the line in question does not define a configuration key: https://github.com/laughinghan/dotfiles/blob/cd846f8069fb10fb25df072da50ec6d9f25f98e7/.gitconfig#L34

Obviously this is a pretty crazy .gitconfig, but it's a valid one, why does cargo build care? Doesn't it just use the system's git? (If you're curious, that crazy alias in question, git sgrep, is like git grep but instead of only searching the repo you're in, it will also recurse into submodules.)

$ git --version
git version 2.10.1 (Apple Git-78)

$ cargo --version --verbose
cargo 0.22.0
release: 0.22.0

$ rustc --version --verbose
rustc 1.22.1
binary: rustc
commit-hash: unknown
commit-date: unknown
host: x86_64-apple-darwin
release: 1.22.1
LLVM version: 4.0

[lukaslueg]

Probably a hickup in libgit. Where does your rustc come from, homebrew or rustup?

[alexcrichton]

Ah yes right now Cargo uses libgit2, not the system git binary. Perhaps this is a bug for libgit2?

[Eh2406]

Did this get resolved? Move to close?

[laughinghan]

Will double-check tonight.

[ehuss]

Filed upstream issue libgit2/libgit2#5459