More tests

Author: oli-obk

tests/ui/consts/dangling_raw_ptr.rs

@@ -22,7 +22,9 @@ const BAZ: Union = { //~ ERROR it is undefined behavior
     Union { ptr: &(&x as *const u32) as *const *const u32 as _ }
 };
 
-fn main() {
-    let x = FOO;
-    let x = BAR;
-}
+const FOOMP: *const u32 = { //~ ERROR it is undefined behavior
+    let x = 42_u32;
+    &(&x as *const u32) as *const *const u32 as _
+};
+
+fn main() {}

tests/ui/consts/dangling_raw_ptr.stderr

@@ -31,6 +31,17 @@ LL | const BAZ: Union = {
                HEX_DUMP
            }
 
-error: aborting due to 3 previous errors
+error[E0080]: it is undefined behavior to use this value
+  --> $DIR/dangling_raw_ptr.rs:25:1
+   |
+LL | const FOOMP: *const u32 = {
+   | ^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .<offset(0)>.<deref>: encountered a dangling reference (use-after-free)
+   |
+   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rustc repository if you believe it should not be considered undefined behavior.
+   = note: the raw bytes of the constant (size: $SIZE, align: $ALIGN) {
+               HEX_DUMP
+           }
+
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0080`.