remove unnessesary argument from start_execution

src/func.rs

@@ -138,7 +138,7 @@ impl FuncInstance {
 		check_function_args(func.signature(), &args)?;
 		match *func.as_internal() {
 			FuncInstanceInternal::Internal { .. } => {
-				interpreter.start_execution(externals, func, args, func.signature().return_type())
+				interpreter.start_execution(externals, func, args)
 			}
 			FuncInstanceInternal::Host {
 				ref host_func_index, ..
@@ -268,14 +268,13 @@ impl FuncInvocation {
 		externals: &'externals mut E,
 		func: &FuncRef,
 		args: &[RuntimeValue],
-		return_type: Option<ValueType>,
 	) -> Result<Option<RuntimeValue>, ResumableError> {
 		match self.kind {
 			FuncInvocationKind::Internal(ref mut interpreter) => {
 				if interpreter.state() != &InterpreterState::Initialized {
 					return Err(ResumableError::AlreadyStarted);
 				}
-				Ok(interpreter.start_execution(externals, func, args, return_type)?)
+				Ok(interpreter.start_execution(externals, func, args)?)
 			}
 			FuncInvocationKind::Host {
 				ref mut finished,

src/runner.rs

@@ -204,10 +204,7 @@ impl Interpreter {
 		externals: &mut E,
 		func: &FuncRef,
 		args: &[RuntimeValue],
-		return_type: Option<ValueType>,
 	) -> Result<Option<RuntimeValue>, Trap> {
-		debug_assert_eq!(func.signature().return_type(), return_type);
-
 		// Ensure that the VM has not been executed. This is checked in `FuncInvocation::start_execution`.
 		assert!(self.state == InterpreterState::Initialized);
 
@@ -224,7 +221,10 @@ impl Interpreter {
 		self.state = InterpreterState::Started;
 		self.run_interpreter_loop(externals)?;
 
-		let opt_return_value = return_type.map(|vt| self.value_stack.pop().with_type(vt));
+		let opt_return_value = func
+			.signature()
+			.return_type()
+			.map(|vt| self.value_stack.pop().with_type(vt));
 
 		// Ensure that stack is empty after the execution. This is guaranteed by the validation properties.
 		assert!(self.value_stack.len() == 0);

src/tests/host.rs

@@ -267,7 +267,7 @@ fn resume_call_host_func() {
 	let return_type = func_instance.signature().return_type();
 
 	let mut invocation = FuncInstance::invoke_resumable(&func_instance);
-	let result = invocation.start_execution(&mut env, func_instance, &[], return_type);
+	let result = invocation.start_execution(&mut env, func_instance, &[]);
 	match result {
 		Err(ResumableError::Trap(_)) => {}
 		_ => panic!(),