Fix some rustc tests

* Check for `#[rustc_error]` attribute.
* Use the same weak static type error message as cg_llvm

Author: bjorn3

src/constant.rs

@@ -202,7 +202,7 @@ fn data_id_for_static(
     if linkage == Linkage::Preemptible {
         if let ty::RawPtr(_) = tcx.type_of(def_id).sty {
         } else {
-            tcx.sess.span_fatal(tcx.def_span(def_id), "must have type `*const T` or `*mut T`")
+            tcx.sess.span_fatal(tcx.def_span(def_id), "must have type `*const T` or `*mut T` due to `#[linkage]` attribute")
         }
 
         let mut data_ctx = DataContext::new();

src/lib.rs

@@ -195,6 +195,8 @@ impl CodegenBackend for CraneliftCodegenBackend {
         need_metadata_module: bool,
         _rx: mpsc::Receiver<Box<dyn Any + Send>>,
     ) -> Box<dyn Any> {
+        rustc_codegen_utils::check_for_rustc_errors_attr(tcx);
+
         let res = driver::codegen_crate(tcx, metadata, need_metadata_module);
 
         rustc_incremental::assert_module_sources::assert_module_sources(tcx);