Create a dummy .git file so that our VERSION is used

Fixes #76

Signed-off-by: Rafael Ávila de Espíndola <[email protected]>

jemalloc-sys/build.rs

@@ -155,6 +155,17 @@ fn main() {
             .expect("failed to copy config file to OUT_DIR");
     }
 
+    // Create a dummy .git file so that 'git describe' fails and
+    // configure uses the VERSION file we provide.
+    if let Err(e) = fs::File::create(build_dir.join(".git")) {
+        // Assume that, if .git is a directory, it is valid and
+        // configure will do the right thing.
+        //  std::io::ErrorKind::IsADirectory is unstable :-(
+        if e.kind().to_string() != "is a directory" {
+            panic!("failed to create a dummy .git file: {}", e);
+        }
+    }
+
     // Run configure:
     let configure = build_dir.join("configure");
     let mut cmd = Command::new("sh");