Vendor dependencies

Let's see how I like this workflow.

vendor/pin-project-lite/tests/ui/pin_project/packed.rs

@@ -0,0 +1,21 @@
+#![allow(unaligned_references)]
+
+use pin_project_lite::pin_project;
+
+pin_project! { //~ ERROR reference to packed field is unaligned
+    #[repr(packed, C)]
+    struct Packed {
+        #[pin]
+        field: u16,
+    }
+}
+
+pin_project! { //~ ERROR reference to packed field is unaligned
+    #[repr(packed(2))]
+    struct PackedN {
+        #[pin]
+        field: u32,
+    }
+}
+
+fn main() {}