Add regression test for SimplifyBranchSame miscompilation

richkadel · Oct 4, 2020 · f271957 · f271957
1 parent 80d5017
commit f271957
Showing 1 changed file with 21 additions and 0 deletions.
diff --git a/src/test/ui/mir/simplify-branch-same.rs b/src/test/ui/mir/simplify-branch-same.rs
@@ -0,0 +1,21 @@
+// Regression test for SimplifyBranchSame miscompilation.
+// run-pass
+
+macro_rules! m {
+    ($a:expr, $b:expr, $c:block) => {
+        match $a {
+            Lto::Fat | Lto::Thin => { $b; (); $c }
+            Lto::No => { $b; () }
+        }
+    }
+}
+
+pub enum Lto { No, Thin, Fat }
+
+fn f(mut cookie: u32, lto: Lto) -> u32 {
+    let mut _a = false;
+    m!(lto, _a = true, {cookie = 0});
+    cookie
+}
+
+fn main() { assert_eq!(f(42, Lto::Thin), 0) }