git cloning in build.rs??

[nc7s]

tcmalloc-rs/tcmalloc-sys/build.rs

Lines 6 to 7 in f81f326

	static TCMALLOC_REPO: &str = "https://github.com/gperftools/gperftools";
	static TCMALLOC_TAG: &str = "gperftools-2.7";

tcmalloc-rs/tcmalloc-sys/build.rs

Lines 37 to 43 in f81f326

	if !out_dir.join("gperftools").exists() {
	assert!(out_dir.exists(), "OUT_DIR does not exist");
	let mut cmd = Command::new("git");
	cmd.current_dir(&out_dir)
	.args(&["clone", TCMALLOC_REPO, "--depth=1", "--branch", TCMALLOC_TAG]);
	run(&mut cmd);
	}

This is unreliable. Check git submodule, or consider vendoring the two files that's actually used.