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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /src/test/ui/union/union-unsafe.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--src/test/ui/union/union-unsafe.rs78
1 files changed, 78 insertions, 0 deletions
diff --git a/src/test/ui/union/union-unsafe.rs b/src/test/ui/union/union-unsafe.rs
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+// revisions: mir thir
+// [thir]compile-flags: -Z thir-unsafeck
+
+use std::mem::ManuallyDrop;
+use std::cell::RefCell;
+
+union U1 {
+ a: u8
+}
+
+union U2 {
+ a: ManuallyDrop<String>
+}
+
+union U3<T> {
+ a: ManuallyDrop<T>
+}
+
+union U4<T: Copy> {
+ a: T
+}
+
+union URef {
+ p: &'static mut i32,
+}
+
+union URefCell { // field that does not drop but is not `Copy`, either
+ a: (ManuallyDrop<RefCell<i32>>, i32),
+}
+
+fn deref_union_field(mut u: URef) {
+ // Not an assignment but an access to the union field!
+ *(u.p) = 13; //~ ERROR access to union field is unsafe
+}
+
+fn assign_noncopy_union_field(mut u: URefCell) {
+ // FIXME(thir-unsafeck)
+ u.a = (ManuallyDrop::new(RefCell::new(0)), 1); // OK (assignment does not drop)
+ u.a.0 = ManuallyDrop::new(RefCell::new(0)); // OK (assignment does not drop)
+ u.a.1 = 1; // OK
+}
+
+fn generic_noncopy<T: Default>() {
+ let mut u3 = U3 { a: ManuallyDrop::new(T::default()) };
+ u3.a = ManuallyDrop::new(T::default()); // OK (assignment does not drop)
+ *u3.a = T::default(); //~ ERROR access to union field is unsafe
+}
+
+fn generic_copy<T: Copy + Default>() {
+ let mut u3 = U3 { a: ManuallyDrop::new(T::default()) };
+ u3.a = ManuallyDrop::new(T::default()); // OK
+ *u3.a = T::default(); //~ ERROR access to union field is unsafe
+
+ let mut u4 = U4 { a: T::default() };
+ u4.a = T::default(); // OK
+}
+
+fn main() {
+ let mut u1 = U1 { a: 10 }; // OK
+ let a = u1.a; //~ ERROR access to union field is unsafe
+ u1.a = 11; // OK
+
+ let U1 { a } = u1; //~ ERROR access to union field is unsafe
+ if let U1 { a: 12 } = u1 {} //~ ERROR access to union field is unsafe
+ // let U1 { .. } = u1; // OK
+
+ let mut u2 = U2 { a: ManuallyDrop::new(String::from("old")) }; // OK
+ u2.a = ManuallyDrop::new(String::from("new")); // OK (assignment does not drop)
+ *u2.a = String::from("new"); //~ ERROR access to union field is unsafe
+
+ let mut u3 = U3 { a: ManuallyDrop::new(0) }; // OK
+ u3.a = ManuallyDrop::new(1); // OK
+ *u3.a = 1; //~ ERROR access to union field is unsafe
+
+ let mut u3 = U3 { a: ManuallyDrop::new(String::from("old")) }; // OK
+ u3.a = ManuallyDrop::new(String::from("new")); // OK (assignment does not drop)
+ *u3.a = String::from("new"); //~ ERROR access to union field is unsafe
+}