[vala/staging: 2/10] codegen: Apply gconstpointer to gpointer cast to GenericType only

[Rico Tzschichholz <ricotz src gnome org>]

commit edc0b532d9469d21fdd91f1b0d0e4d0bcb4045d5
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sun Apr 18 21:02:21 2021 +0200

    codegen: Apply gconstpointer to gpointer cast to GenericType only

 codegen/valaccodebasemodule.vala | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 1fe5e1a37..2d24faba1 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -4791,15 +4791,17 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
                        }
 
                        CCodeExpression cifnull;
-                       if (type.type_symbol != null) {
-                               cifnull = new CCodeConstant ("NULL");
-                       } else {
+                       if (type is GenericType) {
                                // the value might be non-null even when the dup function is null,
                                // so we may not just use NULL for type parameters
 
                                // cast from gconstpointer to gpointer as methods in
                                // generic classes may not return gconstpointer
                                cifnull = new CCodeCastExpression (cexpr, get_ccode_name (pointer_type));
+                       } else if (type.type_symbol != null) {
+                               cifnull = new CCodeConstant ("NULL");
+                       } else {
+                               cifnull = cexpr;
                        }
 
                        if (is_ref_function_void (type)) {