1 files changed, 6 insertions, 0 deletions
diff --git a/llvm.cpp b/llvm.cpp
index 80aaafb..baa7ed3 100644
--- a/llvm.cpp
+++ b/llvm.cpp
@@ -540,6 +540,12 @@ eval(CEnv& cenv, const string& name, istream& is)
 			// Add definitions as GC roots
 			if (result->to<ADefinition*>())
 				cenv.lock(result);
+
+			// Add types in type substition as GC roots
+			for (Subst::iterator i = cenv.tsubst.begin(); i != cenv.tsubst.end(); ++i) {
+				Object::pool.addRoot(i->first);
+				Object::pool.addRoot(i->second);
+			}
 		}
 
 		const Type* ctype = lltype(resultType);