Merging upstream version 1.72.1+dfsg1.

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

1 files changed, 51 insertions, 0 deletions

diff --git a/tests/ui/lint/reference_casting.rs b/tests/ui/lint/reference_casting.rs
new file mode 100644
index 000000000..996382049
--- /dev/null
+++ b/tests/ui/lint/reference_casting.rs
@@ -0,0 +1,51 @@
+// check-fail
+
+#![feature(ptr_from_ref)]
+#![deny(invalid_reference_casting)]
+
+extern "C" {
+    // N.B., mutability can be easily incorrect in FFI calls -- as
+    // in C, the default is mutable pointers.
+    fn ffi(c: *mut u8);
+    fn int_ffi(c: *mut i32);
+}
+
+fn main() {
+    let s = String::from("Hello");
+    let a = &s;
+    unsafe {
+        let num = &3i32;
+        let mut_num = &mut 3i32;
+
+        (*(a as *const _ as *mut String)).push_str(" world");
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        *(a as *const _ as *mut _) = String::from("Replaced");
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        *(a as *const _ as *mut String) += " world";
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        let _num = &mut *(num as *const i32 as *mut i32);
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        let _num = &mut *(num as *const i32).cast_mut();
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        let _num = *{ num as *const i32 }.cast_mut();
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        *std::ptr::from_ref(num).cast_mut() += 1;
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        *std::ptr::from_ref({ num }).cast_mut() += 1;
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        *{ std::ptr::from_ref(num) }.cast_mut() += 1;
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+        *(std::ptr::from_ref({ num }) as *mut i32) += 1;
+        //~^ ERROR casting `&T` to `&mut T` is undefined behavior
+
+        // Shouldn't be warned against
+        println!("{}", *(num as *const _ as *const i16));
+        println!("{}", *(mut_num as *mut _ as *mut i16));
+        ffi(a.as_ptr() as *mut _);
+        int_ffi(num as *const _ as *mut _);
+        int_ffi(&3 as *const _ as *mut _);
+        let mut value = 3;
+        let value: *const i32 = &mut value;
+        *(value as *const i16 as *mut i16) = 42;
+    }
+}