From ecf330f39eaed1f798445ae018cfb645517078bc Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Tue, 27 Oct 2020 16:58:08 +0100
Subject: [PATCH] test Box::into_raw aliasing

---
 tests/run-pass/box-pair-to-vec.rs             | 28 ---------
 tests/run-pass/box.rs                         | 60 +++++++++++++++++++
 .../{box-pair-to-vec.stdout => box.stdout}    |  0
 3 files changed, 60 insertions(+), 28 deletions(-)
 delete mode 100644 tests/run-pass/box-pair-to-vec.rs
 create mode 100644 tests/run-pass/box.rs
 rename tests/run-pass/{box-pair-to-vec.stdout => box.stdout} (100%)

diff --git a/tests/run-pass/box-pair-to-vec.rs b/tests/run-pass/box-pair-to-vec.rs
deleted file mode 100644
index 353afb9d321..00000000000
--- a/tests/run-pass/box-pair-to-vec.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-#[repr(C)]
-#[derive(Debug)]
-struct PairFoo {
-    fst: Foo,
-    snd: Foo,
-}
-
-#[derive(Debug)]
-struct Foo(u64);
-fn reinterstruct(box_pair: Box<PairFoo>) -> Vec<Foo> {
-    let ref_pair = Box::leak(box_pair) as *mut PairFoo;
-    let ptr_foo = unsafe { &mut (*ref_pair).fst as *mut Foo };
-    unsafe {
-        Vec::from_raw_parts(ptr_foo, 2, 2)
-    }
-}
-
-fn main() {
-    let pair_foo = Box::new(PairFoo {
-        fst: Foo(42),
-        snd: Foo(1337),
-    });
-    println!("pair_foo = {:?}", pair_foo);
-    for (n, foo) in reinterstruct(pair_foo).into_iter().enumerate() {
-        println!("foo #{} = {:?}", n, foo);
-    }
-}
-
diff --git a/tests/run-pass/box.rs b/tests/run-pass/box.rs
new file mode 100644
index 00000000000..b89c0ac1286
--- /dev/null
+++ b/tests/run-pass/box.rs
@@ -0,0 +1,60 @@
+#![feature(ptr_internals)]
+
+fn main() {
+    into_raw();
+    into_unique();
+    boxed_pair_to_vec();
+}
+
+fn into_raw() { unsafe {
+    let b = Box::new(4i32);
+    let r = Box::into_raw(b);
+
+    // "lose the tag"
+    let r2 = ((r as usize)+0) as *mut i32;
+    *(&mut *r2) = 7;
+
+    // Use original ptr again
+    *(&mut *r) = 17;
+    drop(Box::from_raw(r));
+}}
+
+fn into_unique() { unsafe {
+    let b = Box::new(4i32);
+    let u = Box::into_unique(b);
+
+    // "lose the tag"
+    let r = ((u.as_ptr() as usize)+0) as *mut i32;
+    *(&mut *r) = 7;
+
+    // Use original ptr again.
+    drop(Box::from_raw(u.as_ptr()));
+}}
+
+fn boxed_pair_to_vec() {
+    #[repr(C)]
+    #[derive(Debug)]
+    struct PairFoo {
+        fst: Foo,
+        snd: Foo,
+    }
+
+    #[derive(Debug)]
+    struct Foo(u64);
+    fn reinterstruct(box_pair: Box<PairFoo>) -> Vec<Foo> {
+        let ref_pair = Box::leak(box_pair) as *mut PairFoo;
+        let ptr_foo = unsafe { &mut (*ref_pair).fst as *mut Foo };
+        unsafe {
+            Vec::from_raw_parts(ptr_foo, 2, 2)
+        }
+    }
+
+    let pair_foo = Box::new(PairFoo {
+        fst: Foo(42),
+        snd: Foo(1337),
+    });
+    println!("pair_foo = {:?}", pair_foo);
+    for (n, foo) in reinterstruct(pair_foo).into_iter().enumerate() {
+        println!("foo #{} = {:?}", n, foo);
+    }
+}
diff --git a/tests/run-pass/box-pair-to-vec.stdout b/tests/run-pass/box.stdout
similarity index 100%
rename from tests/run-pass/box-pair-to-vec.stdout
rename to tests/run-pass/box.stdout
-- 
2.44.0