1 files changed, 6 insertions, 0 deletions
diff --git a/src/tools/tool-options.h b/src/tools/tool-options.h
index bc948fc97..c15291c8d 100644
--- a/src/tools/tool-options.h
+++ b/src/tools/tool-options.h
@@ -176,6 +176,12 @@ struct ToolOptions : public Options {
   void applyFeatures(Module& module) const {
     module.features.enable(enabledFeatures);
     module.features.disable(disabledFeatures);
+    // Non-default type systems only make sense with GC enabled. TODO: Error on
+    // non-GC equirecursive types as well once we make isorecursive the default
+    // if we don't remove equirecursive types entirely.
+    if (!module.features.hasGC() && getTypeSystem() == TypeSystem::Nominal) {
+      Fatal() << "Nominal typing is only allowed when GC is enabled";
+    }
   }
 
 private: