make &mut !Unpin not dereferenceable

See https://github.com/rust-lang/unsafe-code-guidelines/issues/381 for discussion.

1 files changed, 15 insertions, 1 deletions

diff --git a/tests/codegen/function-arguments.rs b/tests/codegen/function-arguments.rs
index 1f979d7b90a..0f4639086b8 100644
--- a/tests/codegen/function-arguments.rs
+++ b/tests/codegen/function-arguments.rs
@@ -85,6 +85,12 @@ pub fn option_nonzero_int(x: Option<NonZeroU64>) -> Option<NonZeroU64> {
 pub fn readonly_borrow(_: &i32) {
 }
 
+// CHECK: noundef align 4 dereferenceable(4) {{i32\*|ptr}} @readonly_borrow_ret()
+#[no_mangle]
+pub fn readonly_borrow_ret() -> &'static i32 {
+  loop {}
+}
+
 // CHECK: @static_borrow({{i32\*|ptr}} noalias noundef readonly align 4 dereferenceable(4) %_1)
 // static borrow may be captured
 #[no_mangle]
@@ -115,9 +121,17 @@ pub fn mutable_unsafe_borrow(_: &mut UnsafeInner) {
 pub fn mutable_borrow(_: &mut i32) {
 }
 
+// CHECK: noundef align 4 dereferenceable(4) {{i32\*|ptr}} @mutable_borrow_ret()
+#[no_mangle]
+pub fn mutable_borrow_ret() -> &'static mut i32 {
+  loop {}
+}
+
 #[no_mangle]
-// CHECK: @mutable_notunpin_borrow({{i32\*|ptr}} noundef align 4 dereferenceable(4) %_1)
+// CHECK: @mutable_notunpin_borrow({{i32\*|ptr}} noundef nonnull align 4 %_1)
 // This one is *not* `noalias` because it might be self-referential.
+// It is also not `dereferenceable` due to
+// <https://github.com/rust-lang/unsafe-code-guidelines/issues/381>.
 pub fn mutable_notunpin_borrow(_: &mut NotUnpin) {
 }