Fix cross-compilation

CHANGELOG.md

@@ -9,7 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-### Fixedw
+### Fixed
+
+* Passing `--target` to build command when cross-compiling.
 
 ### Changed
 

src/lib.rs

@@ -520,6 +520,20 @@ fn build_command(
         cmd.arg("--edition").arg(&*edition);
     }
 
+    if let Some(target) = &config.target {
+        // Adding a `--target` arg to calls to Cargo will cause target folders
+        // to create a target-specific sub-folder. We can avoid that by just
+        // not passing a `--target` arg if its the same as the host.
+        if target
+            != config
+                .host
+                .as_ref()
+                .expect("host should have been filled in")
+        {
+            cmd.arg("--target").arg(target);
+        }
+    }
+
     // False positive in miri, our `map` uses a ref pattern to get the references to the tuple fields instead
     // of a reference to a tuple
     #[allow(clippy::map_identity)]