1 files changed, 8 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/regexp/bug1640487.js b/js/src/jit-test/tests/regexp/bug1640487.js
new file mode 100644
index 0000000000..7ee3756075
--- /dev/null
+++ b/js/src/jit-test/tests/regexp/bug1640487.js
@@ -0,0 +1,8 @@
+var re = /(?<x>a)|b/;
+
+function f(j) {
+    var s = String.fromCharCode(0x61 + (j === 1));
+    var e = re.exec(s);
+    if (e.groups.x !== "a") print(i,j);
+}
+for (var i = 0; i < 2; ++i) f(i);