[vala/staging] codegen: Cast given default-value of struct with possible member initializer

[Rico Tzschichholz <ricotz src gnome org>]

commit 29470dbcfc149d241886dcecb7fd6f4207dc7917
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Mon Jan 3 13:59:36 2022 +0100

    codegen: Cast given default-value of struct with possible member initializer
    
    Fixes https://gitlab.gnome.org/GNOME/vala/issues/1272

 codegen/valaccodebasemodule.vala                   |  6 ++-
 tests/structs/simple-type-default-value.c-expected | 56 ++++++++++++++++++++++
 tests/structs/simple-type-default-value.vala       | 14 ++++++
 3 files changed, 75 insertions(+), 1 deletion(-)
---
diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 2e7df70d5..db9a498cc 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -6544,7 +6544,11 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
                var array_type = type as ArrayType;
                if (type.type_symbol != null && !type.nullable
                    && (on_error ? get_ccode_default_value_on_error (type.type_symbol) : 
get_ccode_default_value (type.type_symbol)) != "") {
-                       return new CCodeConstant (on_error ? get_ccode_default_value_on_error 
(type.type_symbol) : get_ccode_default_value (type.type_symbol));
+                   CCodeExpression val = new CCodeConstant (on_error ? get_ccode_default_value_on_error 
(type.type_symbol) : get_ccode_default_value (type.type_symbol));
+                   if (st != null && st.get_fields ().size > 0) {
+                               val = new CCodeCastExpression (val, get_ccode_name (st));
+                       }
+                       return val;
                } else if (initializer_expression && !type.nullable &&
                                   (st != null || (array_type != null && array_type.fixed_length))) {
                        // 0-initialize struct with struct initializer { 0 }
diff --git a/tests/structs/simple-type-default-value.c-expected 
b/tests/structs/simple-type-default-value.c-expected
new file mode 100644
index 000000000..a9a58bbab
--- /dev/null
+++ b/tests/structs/simple-type-default-value.c-expected
@@ -0,0 +1,56 @@
+/* structs_simple_type_default_value.c generated by valac, the Vala compiler
+ * generated from structs_simple_type_default_value.vala, do not modify */
+
+#include <glib.h>
+#include <glib-object.h>
+
+#if !defined(VALA_EXTERN)
+#if defined(_MSC_VER)
+#define VALA_EXTERN __declspec(dllexport) extern
+#elif __GNUC__ >= 4
+#define VALA_EXTERN __attribute__((visibility("default"))) extern
+#else
+#define VALA_EXTERN extern
+#endif
+#endif
+
+typedef struct _Foo Foo;
+#define _vala_assert(expr, msg) if G_LIKELY (expr) ; else g_assertion_message_expr (G_LOG_DOMAIN, __FILE__, 
__LINE__, G_STRFUNC, msg);
+#define _vala_return_if_fail(expr, msg) if G_LIKELY (expr) ; else { g_return_if_fail_warning (G_LOG_DOMAIN, 
G_STRFUNC, msg); return; }
+#define _vala_return_val_if_fail(expr, msg, val) if G_LIKELY (expr) ; else { g_return_if_fail_warning 
(G_LOG_DOMAIN, G_STRFUNC, msg); return val; }
+#define _vala_warn_if_fail(expr, msg) if G_LIKELY (expr) ; else g_warn_message (G_LOG_DOMAIN, __FILE__, 
__LINE__, G_STRFUNC, msg);
+
+struct _Foo {
+       gint i;
+};
+
+VALA_EXTERN Foo bar (GObject* o);
+static void _vala_main (void);
+
+Foo
+bar (GObject* o)
+{
+       Foo _tmp0_ = (Foo) { .i = 23 };
+       Foo result = (Foo) { .i = 23 };
+       g_return_val_if_fail (G_TYPE_CHECK_INSTANCE_TYPE (o, G_TYPE_OBJECT), (Foo) { .i = 23 });
+       result = _tmp0_;
+       return result;
+}
+
+static void
+_vala_main (void)
+{
+       Foo foo = (Foo) { .i = 23 };
+       Foo _tmp0_ = (Foo) { .i = 23 };
+       foo = _tmp0_;
+       _vala_assert (foo.i == 23, "foo.i == 23");
+}
+
+int
+main (int argc,
+      char ** argv)
+{
+       _vala_main ();
+       return 0;
+}
+
diff --git a/tests/structs/simple-type-default-value.vala b/tests/structs/simple-type-default-value.vala
new file mode 100644
index 000000000..63c21bdd2
--- /dev/null
+++ b/tests/structs/simple-type-default-value.vala
@@ -0,0 +1,14 @@
+[CCode (default_value = "{ .i = 23 }")]
+[SimpleType]
+public struct Foo {
+       int i;
+}
+
+Foo bar (Object o) {
+       return {};
+}
+
+void main () {
+       Foo foo = {};
+       assert (foo.i == 23);
+}