@@ -2,4 +2,4 @@
 "webpack": patch
 ---
 
-Match acorn on `**` arrows, LS/PS cooking, string export names, `program` reuse.
+Match acorn on `**` arrows, LS/PS cooking, string export names, `program` reuse; serialize parse-error locations.
@@ -11686,6 +11686,7 @@ const collectCjsRequireSpecifiers = (source) => {
 };
 
 module.exports.LEGACY_ASSERT_ATTRIBUTES = LEGACY_ASSERT_ATTRIBUTES;
+module.exports.ParserPosition = ParserPosition;
 module.exports.WebpackParser = WebpackParser;
 module.exports.buildLineStarts = buildLineStarts;
 module.exports.collectCjsRequireSpecifiers = collectCjsRequireSpecifiers;
 
@@ -17,6 +17,7 @@ const {
 	ReplaceSource,
 	SourceMapSource
 } = require("webpack-sources");
+const ParserPosition = require("../javascript/syntax").ParserPosition;
 const { register } = require("./serialization");
 
 /** @typedef {import("acorn").Position} Position */
@@ -294,6 +295,36 @@ register(
 	})()
 );
 
+register(
+	ParserPosition,
+	CURRENT_MODULE,
+	"webpack/ParserPosition",
+	new (class ParserPositionSerializer {
+		/**
+		 * Serializes this instance into the provided serializer context.
+		 * @param {ParserPosition} pos the position to be serialized
+		 * @param {import("../serialization/ObjectMiddleware").ObjectSerializerContext<number[]>} context context
+		 * @returns {void}
+		 */
+		serialize(pos, { write }) {
+			write(pos.line);
+			write(pos.column);
+		}
+
+		/**
+		 * Restores this instance from the provided deserializer context.
+		 * @param {import("../serialization/ObjectMiddleware").ObjectDeserializerContext<number[]>} context context
+		 * @returns {SourcePosition} position
+		 */
+		deserialize({ read }) {
+			return {
+				line: read(),
+				column: read()
+			};
+		}
+	})()
+);
+
 register(
 	SourceMapSource,
 	CURRENT_MODULE,