about summary refs log tree commit diff
path: root/tests/ui/union/union-overwrite.rs
diff options
context:
space:
mode:
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/union/union-overwrite.rs
parentca855e6e42787ecd062d81d53336fe6788ef51a9 (diff)
downloadrust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.tar.gz
rust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.zip
Move /src/test to /tests
Diffstat (limited to 'tests/ui/union/union-overwrite.rs')
-rw-r--r--tests/ui/union/union-overwrite.rs80
1 files changed, 80 insertions, 0 deletions
diff --git a/tests/ui/union/union-overwrite.rs b/tests/ui/union/union-overwrite.rs
new file mode 100644
index 00000000000..0eea14d9de0
--- /dev/null
+++ b/tests/ui/union/union-overwrite.rs
@@ -0,0 +1,80 @@
+// run-pass
+// revisions: mirunsafeck thirunsafeck
+// [thirunsafeck]compile-flags: -Z thir-unsafeck
+
+#[repr(C)]
+#[derive(Copy, Clone)]
+struct Pair<T, U>(T, U);
+#[repr(C)]
+#[derive(Copy, Clone)]
+struct Triple<T>(T, T, T);
+
+#[repr(C)]
+union U<A, B>
+where
+    A: Copy, B: Copy
+{
+    a: Pair<A, A>,
+    b: B,
+}
+
+#[repr(C)]
+union W<A, B>
+where
+    A: Copy, B: Copy
+{
+    a: A,
+    b: B,
+}
+
+#[cfg(target_endian = "little")]
+unsafe fn check() {
+    let mut u = U::<u8, u16> { b: 0xDE_DE };
+    u.a.0 = 0xBE;
+    assert_eq!(u.b, 0xDE_BE);
+
+    let mut u = U::<u16, u32> { b: 0xDEAD_DEAD };
+    u.a.0 = 0xBEEF;
+    assert_eq!(u.b, 0xDEAD_BEEF);
+
+    let mut u = U::<u32, u64> { b: 0xDEADBEEF_DEADBEEF };
+    u.a.0 = 0xBAADF00D;
+    assert_eq!(u.b, 0xDEADBEEF_BAADF00D);
+
+    let mut w = W::<Pair<Triple<u8>, u8>, u32> { b: 0xDEAD_DEAD };
+    w.a.0 = Triple(0, 0, 0);
+    assert_eq!(w.b, 0xDE00_0000);
+
+    let mut w = W::<Pair<u8, Triple<u8>>, u32> { b: 0xDEAD_DEAD };
+    w.a.1 = Triple(0, 0, 0);
+    assert_eq!(w.b, 0x0000_00AD);
+}
+
+#[cfg(target_endian = "big")]
+unsafe fn check() {
+    let mut u = U::<u8, u16> { b: 0xDE_DE };
+    u.a.0 = 0xBE;
+    assert_eq!(u.b, 0xBE_DE);
+
+    let mut u = U::<u16, u32> { b: 0xDEAD_DEAD };
+    u.a.0 = 0xBEEF;
+    assert_eq!(u.b, 0xBEEF_DEAD);
+
+    let mut u = U::<u32, u64> { b: 0xDEADBEEF_DEADBEEF };
+    u.a.0 = 0xBAADF00D;
+    assert_eq!(u.b, 0xBAADF00D_DEADBEEF);
+
+    let mut w = W::<Pair<Triple<u8>, u8>, u32> { b: 0xDEAD_DEAD };
+    w.a.0 = Triple(0, 0, 0);
+    assert_eq!(w.b, 0x0000_00AD);
+
+    let mut w = W::<Pair<u8, Triple<u8>>, u32> { b: 0xDEAD_DEAD };
+    w.a.1 = Triple(0, 0, 0);
+    assert_eq!(w.b, 0xDE00_0000);
+}
+
+fn main() {
+    unsafe {
+        check();
+    }
+}