de-orphan extended information

Bizarrely, librustc_passes, librustc_plugin, librustc_mir, and libsyntax
weren't getting their error explanations registered.

Resolves #35284.

src/librustc_driver/lib.rs

@@ -1207,6 +1207,10 @@ pub fn diagnostics_registry() -> errors::registry::Registry {
     all_errors.extend_from_slice(&rustc_trans::DIAGNOSTICS);
     all_errors.extend_from_slice(&rustc_const_eval::DIAGNOSTICS);
     all_errors.extend_from_slice(&rustc_metadata::DIAGNOSTICS);
+    all_errors.extend_from_slice(&rustc_passes::DIAGNOSTICS);
+    all_errors.extend_from_slice(&rustc_plugin::DIAGNOSTICS);
+    all_errors.extend_from_slice(&rustc_mir::DIAGNOSTICS);
+    all_errors.extend_from_slice(&syntax::DIAGNOSTICS);
 
     Registry::new(&all_errors)
 }

src/librustc_mir/lib.rs

@@ -57,3 +57,5 @@ pub fn provide(providers: &mut Providers) {
     shim::provide(providers);
     transform::provide(providers);
 }
+
+__build_diagnostic_array! { librustc_mir, DIAGNOSTICS }

src/librustc_passes/lib.rs

@@ -45,3 +45,5 @@ pub mod loops;
 pub mod mir_stats;
 pub mod no_asm;
 pub mod static_recursion;
+
+__build_diagnostic_array! { librustc_passes, DIAGNOSTICS }

src/librustc_plugin/lib.rs

@@ -84,3 +84,5 @@ pub mod diagnostics;
 pub mod registry;
 pub mod load;
 pub mod build;
+
+__build_diagnostic_array! { librustc_plugin, DIAGNOSTICS }

src/libsyntax/lib.rs

@@ -148,4 +148,4 @@ pub mod ext {
 #[cfg(test)]
 mod test_snippet;
 
-// __build_diagnostic_array! { libsyntax, DIAGNOSTICS }
+__build_diagnostic_array! { libsyntax, DIAGNOSTICS }