[vala/0.50] codegen: Correctly retrieve symbol_reference of nested cast expressions

[Rico Tzschichholz <ricotz src gnome org>]

commit 1cfad14c04faed13b88bc00c4ee27210754b56a0
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sun Feb 7 08:57:39 2021 +0100

    codegen: Correctly retrieve symbol_reference of nested cast expressions
    
    Regression of 63551acaf0d83fac8b50904c2759c1098fbfaa71
    
    Fixes https://gitlab.gnome.org/GNOME/vala/issues/1134

 codegen/valaccodebasemodule.vala      | 7 ++++++-
 tests/generics/integer-type-cast.vala | 9 +++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)
---
diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index c2127094d..171c6f0fb 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -5397,7 +5397,12 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
                var innercexpr = get_cvalue (expr.inner);
                if (expr.type_reference is ValueType && !expr.type_reference.nullable &&
                        expr.inner.value_type is ValueType && expr.inner.value_type.nullable) {
-                       if (!(expr.inner.symbol_reference is Variable)) {
+                       // handle nested cast expressions
+                       unowned Expression? inner_expr = expr.inner;
+                       while (inner_expr is CastExpression) {
+                               inner_expr = ((CastExpression) inner_expr).inner;
+                       }
+                       if (!(inner_expr.symbol_reference is Variable)) {
                                // heap allocated struct leaked, destroy it
                                var value = new GLibValue (new PointerType (new VoidType ()), innercexpr);
                                temp_ref_values.insert (0, value);
diff --git a/tests/generics/integer-type-cast.vala b/tests/generics/integer-type-cast.vala
index 4d7ea8ba6..5e3855aa5 100644
--- a/tests/generics/integer-type-cast.vala
+++ b/tests/generics/integer-type-cast.vala
@@ -3,7 +3,16 @@ void foo<G,T> (G g, T t) {
        assert ((uint64?) t == uint64.MAX);
 }
 
+void bar<G,T> (G g, T t) {
+       assert ((int?) g == int.MIN);
+       assert ((uint?) t == uint.MAX);
+       assert ((int) ((int?) g) == int.MIN);
+       assert ((uint) ((uint?) t) == uint.MAX);
+}
+
 void main () {
        foo ((int64?) int64.MIN, (uint64?) uint64.MAX);
        foo<int64?,uint64?> ((int64?) int64.MIN, (uint64?) uint64.MAX);
+       bar ((int?) int.MIN, (uint?) uint.MAX);
+       bar<int?,uint?> ((int?) int.MIN, (uint?) uint.MAX);
 }