diff --git a/packages/gatsby-cli/src/structured-errors/error-schema.ts b/packages/gatsby-cli/src/structured-errors/error-schema.ts
index 306da6d31bdee..d018c061e91c8 100644
--- a/packages/gatsby-cli/src/structured-errors/error-schema.ts
+++ b/packages/gatsby-cli/src/structured-errors/error-schema.ts
@@ -27,7 +27,7 @@ export const errorSchema: Joi.ObjectSchema<IStructuredError> =
     location: Joi.object({
       start: Position.required(),
       end: Position,
-    }),
+    }).unknown(),
     docsUrl: Joi.string().uri({
       allowRelative: false,
       relativeOnly: false,
diff --git a/packages/gatsby/src/utils/webpack-error-utils.ts b/packages/gatsby/src/utils/webpack-error-utils.ts
index ac16ce191921a..9ae9d58994ec1 100644
--- a/packages/gatsby/src/utils/webpack-error-utils.ts
+++ b/packages/gatsby/src/utils/webpack-error-utils.ts
@@ -64,7 +64,10 @@ const transformWebpackError = (
 
   if (!location && castedWebpackError.error?.loc) {
     if (castedWebpackError.error.loc.start) {
-      location = castedWebpackError.error.loc
+      location = {
+        start: castedWebpackError.error.loc.start,
+        end: castedWebpackError.error.loc.end,
+      }
     } else {
       location = {
         start: castedWebpackError.error.loc,