suppress false positives in `ufuzz` (#4419)

1 files changed, 10 insertions, 0 deletions

diff --git a/README.md b/README.md
index 4753b4c2..c23116bd 100644
--- a/README.md
+++ b/README.md
@@ -1217,3 +1217,13 @@ To allow for better optimizations, the compiler makes various assumptions:
   // SyntaxError: Identifier 'a' has already been declared
   ```
   UglifyJS may modify the input which in turn may suppress those errors.
+- Later versions of JavaScript will throw `SyntaxError` with the following:
+  ```js
+  try {
+    // ...
+  } catch ({ message: a }) {
+    var a;
+  }
+  // SyntaxError: Identifier 'a' has already been declared
+  ```
+  UglifyJS may modify the input which in turn may suppress those errors.