PR feedback.

Author: bartchr808

include/swift/AST/DiagnosticsSema.def

@@ -2733,8 +2733,8 @@ ERROR(differentiable_attr_unsupported_req_kind,none,
       "layout requirement are not supported by '@differentiable' attribute", ())
 ERROR(differentiable_attr_class_unsupported,none,
       "class members cannot be marked with '@differentiable'", ())
-ERROR(differentiable_attr_stored_prop_unsupported,none,
-"Stored properties cannot be marked with '@differentiable'", ())
+ERROR(differentiable_attr_stored_property_unsupported,none,
+      "Stored properties cannot be marked with '@differentiable'", ())
 NOTE(protocol_witness_missing_specific_differentiable_attr,none,
      "candidate is missing attribute '%0'", (StringRef))
 

lib/Sema/TypeCheckAttr.cpp

@@ -2888,7 +2888,8 @@ void AttributeChecker::visitDifferentiableAttr(DifferentiableAttr *attr) {
   AbstractFunctionDecl *original = dyn_cast<AbstractFunctionDecl>(D);
   if (auto *asd = dyn_cast<AbstractStorageDecl>(D)) {
     if (asd->getImplInfo().isSimpleStored()) {
-      diagnoseAndRemoveAttr(attr, diag::differentiable_attr_stored_prop_unsupported);
+      diagnoseAndRemoveAttr(attr, diag::differentiable_attr_stored_property_unsupported);
+	  return;
     }
     // When used directly on a storage decl (stored/computed property or
     // subscript), the getter is currently inferred to be `@differentiable`.

test/AutoDiff/differentiating_attr_type_checking.swift

@@ -298,7 +298,7 @@ func vjpConsistent(_ x: Float) -> (value: Float, pullback: (Float) -> Float) {
 
 // Test usage of `@differentiable` on a stored property
 struct PropertyDiff : Differentiable & AdditiveArithmetic {
-	// expected-error @+1 {{Stored properties cannot be marked with '@differentiable'}}
+    // expected-error @+1 {{Stored properties cannot be marked with '@differentiable'}}
     @differentiable(vjp: vjpPropertyA)
     var a: Float = 1
     typealias TangentVector = PropertyDiff