From 206864165524c9e2dc93ef0f70f032c60045406a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dominik=20Inf=C3=BChr?= <dominik.infuehr@gmail.com>
Date: Sat, 25 Jan 2025 13:53:10 +0100
Subject: [PATCH] frontend: Remove register in visit_expr_is

---
 dora-frontend/src/generator.rs |  2 ++
 tests/trait/trait-object3.dora | 26 ++++++++++++++++++++++++++
 2 files changed, 28 insertions(+)
 create mode 100644 tests/trait/trait-object3.dora

diff --git a/dora-frontend/src/generator.rs b/dora-frontend/src/generator.rs
index 6e9ac0427..616cfe7d7 100644
--- a/dora-frontend/src/generator.rs
+++ b/dora-frontend/src/generator.rs
@@ -1243,6 +1243,8 @@ impl<'a> AstBytecodeGen<'a> {
         self.builder.bind_label(merge_lbl);
         self.pop_scope();
 
+        self.free_if_temp(value_reg);
+
         dest
     }
 
diff --git a/tests/trait/trait-object3.dora b/tests/trait/trait-object3.dora
new file mode 100644
index 000000000..941757d47
--- /dev/null
+++ b/tests/trait/trait-object3.dora
@@ -0,0 +1,26 @@
+use std::traits::Iterator;
+
+class Range {
+    value: Int
+}
+
+impl Iterator for Range {
+    type Item = Int;
+
+    fn next(): Option[Int] {
+        if self.value <= 0 {
+            None[Int]
+        } else {
+            let result = self.value;
+            self.value -= 1;
+            Some[Int](result)
+        }
+    }
+}
+
+fn main() {
+    let r = Range(2);
+    assert(r.next() is Some(x) && x == 2);
+    assert(r.next() is Some(x) && x == 1);
+    assert(r.next() is None);
+}