Executing `git rev-parse master` failed

cargo build -u --verbose results in this error on the following step:

   Compiling graphics v0.0.0 (https://github.com/pistondevelopers/rust-graphics)
Executing `git rev-parse master` failed

Caused by:
  Executing `git rev-parse master` failed

Caused by:
  Could not execute process `git rev-parse master` (status=never executed)

Caused by:
  no such file or directory

I have also opened an issue for cargo: rust-lang/cargo#84

[bvssvni]

Error checklist:

• appears with latest Rust nightly
• appears with latest Cargo
• appears on more than one machine

[madjar]

@bvssvni I had the same error last night, and I worked around it by making cargo display the name of the directory it tried to find and symlinking it to the right value.

@madjar can you explain the workaround better?

[madjar]

First, I patched cargo to display the value of self.path there: https://github.com/rust-lang/cargo/blob/master/src/cargo/sources/git/utils.rs#L208

Then I ran cargo-build, it gave me the value of the missing directory. It is of the form ~/.cargo/git/db/graphics-<something>, where <something> is an hexadecimal value. This directory doesn't exist, but one with another hex value exists, so I created a symlink to the existing one. Cargo stopped complaining.

I don't konw what that hex value means, but it looks like it's not computed correctly in Cargo.

The latest cargo update, and writing dependencies as git = "https://github.com/PistonDevelopers/rust-graphics.git" in Cargo.toml (rather than git = "https://github.com/pistondevelopers/rust-graphics")avoids this error.