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authorAlbert Larsan <74931857+albertlarsan68@users.noreply.github.com>2023-01-05 09:13:28 +0100
committerAlbert Larsan <74931857+albertlarsan68@users.noreply.github.com>2023-01-11 09:32:08 +0000
commitcf2dff2b1e3fa55fa5415d524200070d0d7aacfe (patch)
tree40a88d9a46aaf3e8870676eb2538378b75a263eb /tests/ui/generator/drop-and-replace.rs
parentca855e6e42787ecd062d81d53336fe6788ef51a9 (diff)
downloadrust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.tar.gz
rust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.zip
Move /src/test to /tests
Diffstat (limited to 'tests/ui/generator/drop-and-replace.rs')
-rw-r--r--tests/ui/generator/drop-and-replace.rs45
1 files changed, 45 insertions, 0 deletions
diff --git a/tests/ui/generator/drop-and-replace.rs b/tests/ui/generator/drop-and-replace.rs
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+// run-pass
+// Regression test for incorrect DropAndReplace behavior introduced in #60840
+// and fixed in #61373. When combined with the optimization implemented in
+// #60187, this produced incorrect code for generators when a saved local was
+// re-assigned.
+
+#![feature(generators, generator_trait)]
+
+use std::ops::{Generator, GeneratorState};
+use std::pin::Pin;
+
+#[derive(Debug, PartialEq)]
+struct Foo(i32);
+
+impl Drop for Foo {
+    fn drop(&mut self) { }
+}
+
+fn main() {
+    let mut a = || {
+        let mut x = Foo(4);
+        yield;
+        assert_eq!(x.0, 4);
+
+        // At one point this tricked our dataflow analysis into thinking `x` was
+        // StorageDead after the assignment.
+        x = Foo(5);
+        assert_eq!(x.0, 5);
+
+        {
+            let y = Foo(6);
+            yield;
+            assert_eq!(y.0, 6);
+        }
+
+        assert_eq!(x.0, 5);
+    };
+
+    loop {
+        match Pin::new(&mut a).resume(()) {
+            GeneratorState::Complete(()) => break,
+            _ => (),
+        }
+    }
+}