message: A nicer way to hash a pointer
diff: @@ -341,7 +341,7 @@ impl SourceId {
  }
  pub fn full_hash<S: hash::Hasher>(&self, into: &mut S) {
  - (self.inner as *const SourceIdInner).hash(into)
  + ptr::NonNull::from(self.inner).hash(into)
  }
  }
  