Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 130 insertions, 0 deletions

diff --git a/tests/ui/cleanup-rvalue-scopes.rs b/tests/ui/cleanup-rvalue-scopes.rs
new file mode 100644
index 000000000..b80f95b79
--- /dev/null
+++ b/tests/ui/cleanup-rvalue-scopes.rs
@@ -0,0 +1,130 @@
+// run-pass
+#![allow(unused_braces)]
+#![allow(non_snake_case)]
+#![allow(unused_variables)]
+// Test that destructors for rvalue temporaries run either at end of
+// statement or end of block, as appropriate given the temporary
+// lifetime rules.
+
+#![feature(box_patterns)]
+
+use std::ops::Drop;
+
+static mut FLAGS: u64 = 0;
+
+struct Box<T> { f: T }
+struct AddFlags { bits: u64 }
+
+fn AddFlags(bits: u64) -> AddFlags {
+    AddFlags { bits: bits }
+}
+
+fn arg(exp: u64, _x: &AddFlags) {
+    check_flags(exp);
+}
+
+fn pass<T>(v: T) -> T {
+    v
+}
+
+fn check_flags(exp: u64) {
+    unsafe {
+        let x = FLAGS;
+        FLAGS = 0;
+        println!("flags {}, expected {}", x, exp);
+        assert_eq!(x, exp);
+    }
+}
+
+impl AddFlags {
+    fn check_flags<'a>(&'a self, exp: u64) -> &'a AddFlags {
+        check_flags(exp);
+        self
+    }
+
+    fn bits(&self) -> u64 {
+        self.bits
+    }
+}
+
+impl Drop for AddFlags {
+    fn drop(&mut self) {
+        unsafe {
+            FLAGS = FLAGS + self.bits;
+        }
+    }
+}
+
+macro_rules! end_of_block {
+    ($pat:pat, $expr:expr) => (
+        {
+            println!("end_of_block({})", stringify!({let $pat = $expr;}));
+
+            {
+                // Destructor here does not run until exit from the block.
+                let $pat = $expr;
+                check_flags(0);
+            }
+            check_flags(1);
+        }
+    )
+}
+
+macro_rules! end_of_stmt {
+    ($pat:pat, $expr:expr) => (
+        {
+            println!("end_of_stmt({})", stringify!($expr));
+
+            {
+                // Destructor here run after `let` statement
+                // terminates.
+                let $pat = $expr;
+                check_flags(1);
+            }
+
+            check_flags(0);
+        }
+    )
+}
+
+pub fn main() {
+
+    // In all these cases, we trip over the rules designed to cover
+    // the case where we are taking addr of rvalue and storing that
+    // addr into a stack slot, either via `let ref` or via a `&` in
+    // the initializer.
+
+    end_of_block!(_x, AddFlags(1));
+    end_of_block!(_x, &AddFlags(1));
+    end_of_block!(_x, & &AddFlags(1));
+    end_of_block!(_x, Box { f: AddFlags(1) });
+    end_of_block!(_x, Box { f: &AddFlags(1) });
+    end_of_block!(_x, Box { f: &AddFlags(1) });
+    end_of_block!(_x, pass(AddFlags(1)));
+    end_of_block!(ref _x, AddFlags(1));
+    end_of_block!(AddFlags { bits: ref _x }, AddFlags(1));
+    end_of_block!(&AddFlags { bits }, &AddFlags(1));
+    end_of_block!((_, ref _y), (AddFlags(1), 22));
+    end_of_block!(box ref _x, std::boxed::Box::new(AddFlags(1)));
+    end_of_block!(box _x, std::boxed::Box::new(AddFlags(1)));
+    end_of_block!(_, { { check_flags(0); &AddFlags(1) } });
+    end_of_block!(_, &((Box { f: AddFlags(1) }).f));
+    end_of_block!(_, &(([AddFlags(1)])[0]));
+
+    // LHS does not create a ref binding, so temporary lives as long
+    // as statement, and we do not move the AddFlags out:
+    end_of_stmt!(_, AddFlags(1));
+    end_of_stmt!((_, _), (AddFlags(1), 22));
+
+    // `&` operator appears inside an arg to a function,
+    // so it is not prolonged:
+    end_of_stmt!(ref _x, arg(0, &AddFlags(1)));
+
+    // autoref occurs inside receiver, so temp lifetime is not
+    // prolonged:
+    end_of_stmt!(ref _x, AddFlags(1).check_flags(0).bits());
+
+    // No reference is created on LHS, thus RHS is moved into
+    // a temporary that lives just as long as the statement.
+    end_of_stmt!(AddFlags { bits }, AddFlags(1));
+}