diff --git a/libsolidity/codegen/YulUtilFunctions.cpp b/libsolidity/codegen/YulUtilFunctions.cpp
index 8fe11757a..28c72ad05 100644
--- a/libsolidity/codegen/YulUtilFunctions.cpp
+++ b/libsolidity/codegen/YulUtilFunctions.cpp
@@ -3072,6 +3072,12 @@ string YulUtilFunctions::conversionFunction(Type const& _from, Type const& _to)
 				solAssert(false, "Invalid conversion from " + _from.canonicalName() + " to " + _to.canonicalName());
 			break;
 		}
+		case Type::Category::Mapping:
+		{
+			solAssert(_from == _to, "");
+			body = "converted := value";
+			break;
+		}
 		default:
 			solAssert(false, "Invalid conversion from " + _from.canonicalName() + " to " + _to.canonicalName());
 		}
diff --git a/test/libsolidity/semanticTests/variables/mapping_local_tuple_assignment.sol b/test/libsolidity/semanticTests/variables/mapping_local_tuple_assignment.sol
index 39dd04abb..eb5e6b854 100644
--- a/test/libsolidity/semanticTests/variables/mapping_local_tuple_assignment.sol
+++ b/test/libsolidity/semanticTests/variables/mapping_local_tuple_assignment.sol
@@ -12,5 +12,7 @@ contract test {
         return (m1[1], m1[2], m2[1], m2[2]);
     }
 }
+// ====
+// compileViaYul: also
 // ----
 // f() -> 42, 0, 0, 21