Merge pull request #25272 from DougGregor/property-wrappers-default-init-crash-sr-10830

Author: swift-ci

lib/AST/Decl.cpp

@@ -5475,16 +5475,33 @@ bool VarDecl::isPropertyWrapperInitializedWithInitialValue() const {
   if (!ctx.getLazyResolver())
     return false;
 
-  // If there is no initializer, the initialization form depends on
-  // whether the property wrapper type has an init(initialValue:).
-  if (!isParentInitialized()) {
-    auto wrapperTypeInfo = getAttachedPropertyWrapperTypeInfo();
-    return wrapperTypeInfo.initialValueInit != nullptr;
-  }
+  auto customAttr = getAttachedPropertyWrapper();
+  if (!customAttr)
+    return false;
+
+  auto *PBD = getParentPatternBinding();
+  if (!PBD)
+    return false;
+
+  // If there was an initializer on the original property, initialize
+  // via the initial value.
+  if (PBD->getPatternList()[0].getEqualLoc().isValid())
+    return true;
+
+  // If there was an initializer on the attribute itself, initialize
+  // via the full wrapper.
+  if (customAttr->getArg() != nullptr)
+    return false;
 
-  // Otherwise, check whether the '=' initialization form was used.
-  return getPropertyWrapperBackingPropertyInfo().originalInitialValue
-      != nullptr;
+  // If the property wrapper is default-initializable, it's the wrapper
+  // being initialized.
+  if (PBD->isDefaultInitializable(0))
+    return false;
+
+  // There is no initializer, so the initialization form depends on
+  // whether the property wrapper type has an init(initialValue:).
+  auto wrapperTypeInfo = getAttachedPropertyWrapperTypeInfo();
+  return wrapperTypeInfo.initialValueInit != nullptr;
 }
 
 Identifier VarDecl::getObjCPropertyName() const {

test/IDE/print_property_wrappers.swift

@@ -47,7 +47,7 @@ struct HasWrappers {
   var z: String
 
   // Memberwise initializer.
-  // CHECK: init(x: Wrapper<Int> = Wrapper(closure: foo), y: Bool = true, z: String = Wrapper())
+  // CHECK: init(x: Wrapper<Int> = Wrapper(closure: foo), y: Bool = true, z: Wrapper<String> = Wrapper())
 }
 
 func trigger() {

test/SILGen/property_wrappers.swift

@@ -269,6 +269,34 @@ extension ClassUsingWrapper {
   }
 }
 
+// 
+@_propertyWrapper
+struct WrapperWithDefaultInit<T> {
+  private var storage: T?
+
+  init() {
+    self.storage = nil
+  }
+  
+  init(initialValue: T) {
+    self.storage = initialValue
+  }
+
+  var value: T {
+    get { return storage! }
+    set { storage = newValue }
+  }
+}
+
+class UseWrapperWithDefaultInit {
+  @WrapperWithDefaultInit var name: String
+}
+
+// CHECK-LABEL: sil hidden [transparent] [ossa] @$s17property_wrappers25UseWrapperWithDefaultInitC5$name33_F728088E0028E14D18C6A10CF68512E8LLAA0defG0VySSGvpfi : $@convention(thin) () -> @owned WrapperWithDefaultInit<String>
+// CHECK: function_ref @$s17property_wrappers22WrapperWithDefaultInitVACyxGycfC
+// CHECK: return {{%.*}} : $WrapperWithDefaultInit<String>
+
+
 // CHECK-LABEL: sil_vtable ClassUsingWrapper {
 // CHECK:  #ClassUsingWrapper.x!getter.1: (ClassUsingWrapper) -> () -> Int : @$s17property_wrappers17ClassUsingWrapperC1xSivg   // ClassUsingWrapper.x.getter
 // CHECK:  #ClassUsingWrapper.x!setter.1: (ClassUsingWrapper) -> (Int) -> () : @$s17property_wrappers17ClassUsingWrapperC1xSivs // ClassUsingWrapper.x.setter