diff --git a/src/interpreter.c b/src/interpreter.c
index 53d218e..a61d5a6 100644
--- a/src/interpreter.c
+++ b/src/interpreter.c
@@ -79,7 +79,6 @@ int Interpreter_ParseFunction(Interpreter* self, CallFrame* top_frame, size_t st
 
 	Token* function_name = Interpreter_GetToken(self, top_frame->instruction_pointer);
 
-	memset(f, 0, sizeof(*f));
 	f->name = function_name->get.identifier;
 	top_frame->instruction_pointer++;
 
@@ -87,6 +86,7 @@ int Interpreter_ParseFunction(Interpreter* self, CallFrame* top_frame, size_t st
 	top_frame->instruction_pointer++;
 
 	Token* parameter_type = Interpreter_ExpectToken(self, top_frame, stop_index);
+	f->parameters = NULL;
 	ParameterDefinition** pdef = &f->parameters;
 	while (parameter_type->type != TOKENTYPE_ARROW) {
 		top_frame->instruction_pointer++;
@@ -109,6 +109,7 @@ int Interpreter_ParseFunction(Interpreter* self, CallFrame* top_frame, size_t st
 
 		(*pdef)->type = parameter_type->get.identifier;
 		(*pdef)->name = parameter_name->get.identifier;
+		(*pdef)->next = NULL;
 		pdef = &((*pdef)->next);
 
 		parameter_type = Interpreter_ExpectToken(self, top_frame, stop_index);