diff --git a/js/src/jit-test/tests/ion/bug2076269.js b/js/src/jit-test/tests/ion/bug2076269.js
new file mode 100644
index 00000000000..af74a531ad4
--- /dev/null
+++ b/js/src/jit-test/tests/ion/bug2076269.js
@@ -0,0 +1,45 @@
+// |jit-test| --fast-warmup
+
+function test(numProps) {
+  let g = newGlobal({sameCompartmentAs: this});
+  g.eval(`
+    // Throws when called without arguments, so warm-up never creates the
+    // rest array.
+    function inner(a = a, ...rest) { return rest; }
+
+    function outer(global, callInner, value, callee, stored, box) {
+      let before = global.p0;
+      let rest;
+      if (callInner) rest = callee(value);
+      global.p1 = stored;
+      box.rest = rest;
+      box.before = before;
+    }
+
+    var box = {rest: null, before: 0};
+    try { inner(); } catch (e) {}
+
+    for (let i = 0; i < ${numProps}; i++) this["p" + i] = i;
+  `);
+  let box = g.box;
+
+  for (let i = 0; i < 200; i++) {
+    g.p0 = i;
+    try { g.outer(g, true, undefined, g.inner, i, box); } catch (e) {}
+  }
+  for (let i = 0; i < 5000; i++) {
+    g.p0 = i;
+    g.outer(g, false, 123, g.inner, i, box);
+  }
+
+  g.p0 = 7;
+  g.p1 = -1;
+  g.outer(g, true, 123, g.inner, 12345, box);
+
+  assertEq(g.p1, 12345);
+  assertEq(box.rest.length, 0);
+}
+
+for (let numProps = 65110; numProps <= 65130; numProps++) {
+  test(numProps);
+}

diff --git a/js/src/jit-test/tests/ion/bug2076269.js b/js/src/jit-test/tests/ion/bug2076269.js
new file mode 100644
index 00000000000..af74a531ad4
--- /dev/null
+++ b/js/src/jit-test/tests/ion/bug2076269.js
@@ -0,0 +1,45 @@
+// |jit-test| --fast-warmup
+
+function test(numProps) {
+  let g = newGlobal({sameCompartmentAs: this});
+  g.eval(`
+    // Throws when called without arguments, so warm-up never creates the
+    // rest array.
+    function inner(a = a, ...rest) { return rest; }
+
+    function outer(global, callInner, value, callee, stored, box) {
+      let before = global.p0;
+      let rest;
+      if (callInner) rest = callee(value);
+      global.p1 = stored;
+      box.rest = rest;
+      box.before = before;
+    }
+
+    var box = {rest: null, before: 0};
+    try { inner(); } catch (e) {}
+
+    for (let i = 0; i < ${numProps}; i++) this["p" + i] = i;
+  `);
+  let box = g.box;
+
+  for (let i = 0; i < 200; i++) {
+    g.p0 = i;
+    try { g.outer(g, true, undefined, g.inner, i, box); } catch (e) {}
+  }
+  for (let i = 0; i < 5000; i++) {
+    g.p0 = i;
+    g.outer(g, false, 123, g.inner, i, box);
+  }
+
+  g.p0 = 7;
+  g.p1 = -1;
+  g.outer(g, true, 123, g.inner, 12345, box);
+
+  assertEq(g.p1, 12345);
+  assertEq(box.rest.length, 0);
+}
+
+for (let numProps = 65110; numProps <= 65130; numProps++) {
+  test(numProps);
+}