no need to store linked_value if setting

packages/svelte/src/internal/client/reactivity/sources.js

@@ -47,11 +47,14 @@ export function source(v) {
 }
 
 /**
- * @param {() => any} get_value
+ * @template V
+ * @param {() => V} get_value
+ * @returns {(value?: V) => V}
  */
 export function source_link(get_value) {
 	var was_local = false;
 	var local_source = source(undefined);
+
 	var linked_derived = derived(() => {
 		var local_value = get(local_source);
 		var linked_value = get_value();
@@ -65,14 +68,14 @@ export function source_link(get_value) {
 	});
 
 	return function (/** @type {any} */ value) {
-		var linked_value = get(linked_derived);
 		if (arguments.length > 0) {
 			was_local = true;
 			set(local_source, value);
 			get(linked_derived);
 			return value;
 		}
-		return linked_value;
+
+		return get(linked_derived);
 	};
 }