Merge 566742d057 into 36847f6af0

include/godot_cpp/core/memory.hpp

@@ -190,15 +190,24 @@ struct _GlobalNilClass {
 	static _GlobalNil _nil;
 };
 
+// This is for allocating uninitialized memory for passing to GDExtension functions that
+// will use placement new to construct a new object.
+//
+// NOTE: You MUST make sure that the value is initialized before the object goes out of
+// scope, otherwise the destructor will be run on junk memory and "bad things" will happen.
 template <class T, size_t Alignment = alignof(T)>
-class UninitializedValue {
+class ManuallyInitializedValue {
 	typename std::aligned_storage<sizeof(T), Alignment>::type data;
 
 public:
-	UninitializedValue() {}
+	ManuallyInitializedValue() {}
 
-	UninitializedValue(const UninitializedValue &) = delete;
+	ManuallyInitializedValue(const ManuallyInitializedValue &) = delete;
-	UninitializedValue &operator=(const UninitializedValue &) = delete;
+	ManuallyInitializedValue &operator=(const ManuallyInitializedValue &) = delete;
+
+	~ManuallyInitializedValue() {
+		reinterpret_cast<T *>(&data)->~T();
+	}
 
 	T &get() {
 		return *reinterpret_cast<T *>(&data);

src/variant/variant.cpp

@@ -303,9 +303,9 @@ Variant::operator float() const {
 }
 
 Variant::operator String() const {
-	String result;
+	ManuallyInitializedValue<String> result;
-	to_type_constructor[STRING](result._native_ptr(), _native_ptr());
+	to_type_constructor[STRING](result.ptr(), _native_ptr());
-	return result;
+	return result.get();
 }
 
 Variant::operator Vector2() const {
@@ -405,9 +405,9 @@ Variant::operator Color() const {
 }
 
 Variant::operator StringName() const {
-	StringName result;
+	ManuallyInitializedValue<StringName> result;
-	to_type_constructor[STRING_NAME](result._native_ptr(), _native_ptr());
+	to_type_constructor[STRING_NAME](result.ptr(), _native_ptr());
-	return result;
+	return result.get();
 }
 
 Variant::operator NodePath() const {
@@ -459,13 +459,13 @@ Variant::operator Signal() const {
 }
 
 Variant::operator Dictionary() const {
-	UninitializedValue<Dictionary> result;
+	ManuallyInitializedValue<Dictionary> result;
 	to_type_constructor[DICTIONARY](result.ptr(), _native_ptr());
 	return result.get();
 }
 
 Variant::operator Array() const {
-	UninitializedValue<Array> result;
+	ManuallyInitializedValue<Array> result;
 	to_type_constructor[ARRAY](result.ptr(), _native_ptr());
 	return result.get();
 }
@@ -607,39 +607,39 @@ void Variant::set_keyed(const Variant &key, const Variant &value, bool &r_valid)
 }
 
 Variant Variant::get(const Variant &key, bool *r_valid) const {
-	Variant result;
+	ManuallyInitializedValue<Variant> result;
 	GDExtensionBool valid;
-	internal::gdextension_interface_variant_get(_native_ptr(), key._native_ptr(), result._native_ptr(), &valid);
+	internal::gdextension_interface_variant_get(_native_ptr(), key._native_ptr(), result.ptr(), &valid);
 	if (r_valid) {
 		*r_valid = PtrToArg<bool>::convert(&valid);
 	}
-	return result;
+	return result.get();
 }
 
 Variant Variant::get_named(const StringName &name, bool &r_valid) const {
-	Variant result;
+	ManuallyInitializedValue<Variant> result;
 	GDExtensionBool valid;
-	internal::gdextension_interface_variant_get_named(_native_ptr(), name._native_ptr(), result._native_ptr(), &valid);
+	internal::gdextension_interface_variant_get_named(_native_ptr(), name._native_ptr(), result.ptr(), &valid);
 	r_valid = PtrToArg<bool>::convert(&valid);
-	return result;
+	return result.get();
 }
 
 Variant Variant::get_indexed(int64_t index, bool &r_valid, bool &r_oob) const {
-	Variant result;
+	ManuallyInitializedValue<Variant> result;
 	GDExtensionBool valid;
 	GDExtensionBool oob;
-	internal::gdextension_interface_variant_get_indexed(_native_ptr(), index, result._native_ptr(), &valid, &oob);
+	internal::gdextension_interface_variant_get_indexed(_native_ptr(), index, result.ptr(), &valid, &oob);
 	r_valid = PtrToArg<bool>::convert(&valid);
 	r_oob = PtrToArg<bool>::convert(&oob);
-	return result;
+	return result.get();
 }
 
 Variant Variant::get_keyed(const Variant &key, bool &r_valid) const {
-	Variant result;
+	ManuallyInitializedValue<Variant> result;
 	GDExtensionBool valid;
-	internal::gdextension_interface_variant_get_keyed(_native_ptr(), key._native_ptr(), result._native_ptr(), &valid);
+	internal::gdextension_interface_variant_get_keyed(_native_ptr(), key._native_ptr(), result.ptr(), &valid);
 	r_valid = PtrToArg<bool>::convert(&valid);
-	return result;
+	return result.get();
 }
 
 bool Variant::in(const Variant &index, bool *r_valid) const {