Merging upstream version 1.68.2+dfsg1.

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

1 files changed, 71 insertions, 0 deletions

diff --git a/tests/ui/consts/const-eval/ub-ref-ptr.rs b/tests/ui/consts/const-eval/ub-ref-ptr.rs
new file mode 100644
index 000000000..369e45194
--- /dev/null
+++ b/tests/ui/consts/const-eval/ub-ref-ptr.rs
@@ -0,0 +1,71 @@
+// ignore-tidy-linelength
+// Strip out raw byte dumps to make comparison platform-independent:
+// normalize-stderr-test "(the raw bytes of the constant) \(size: [0-9]*, align: [0-9]*\)" -> "$1 (size: $$SIZE, align: $$ALIGN)"
+// normalize-stderr-test "([0-9a-f][0-9a-f] |╾─*a(lloc)?[0-9]+(\+[a-z0-9]+)?─*╼ )+ *│.*" -> "HEX_DUMP"
+#![allow(invalid_value)]
+#![feature(const_ptr_read)]
+
+use std::mem;
+
+#[repr(C)]
+union MaybeUninit<T: Copy> {
+    uninit: (),
+    init: T,
+}
+
+const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) };
+//~^ ERROR it is undefined behavior to use this value
+//~| constructing invalid value: encountered an unaligned reference (required 2 byte alignment but found 1)
+
+const UNALIGNED_BOX: Box<u16> = unsafe { mem::transmute(&[0u8; 4]) };
+//~^ ERROR it is undefined behavior to use this value
+//~| constructing invalid value: encountered an unaligned box (required 2 byte alignment but found 1)
+
+const NULL: &u16 = unsafe { mem::transmute(0usize) };
+//~^ ERROR it is undefined behavior to use this value
+
+const NULL_BOX: Box<u16> = unsafe { mem::transmute(0usize) };
+//~^ ERROR it is undefined behavior to use this value
+
+
+// It is very important that we reject this: We do promote `&(4 * REF_AS_USIZE)`,
+// but that would fail to compile; so we ended up breaking user code that would
+// have worked fine had we not promoted.
+const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) };
+//~^ ERROR evaluation of constant value failed
+
+const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }];
+//~^ ERROR evaluation of constant value failed
+
+const REF_AS_USIZE_BOX_SLICE: Box<[usize]> = unsafe { mem::transmute::<&[usize], _>(&[mem::transmute(&0)]) };
+//~^ ERROR evaluation of constant value failed
+
+const USIZE_AS_REF: &'static u8 = unsafe { mem::transmute(1337usize) };
+//~^ ERROR it is undefined behavior to use this value
+
+const USIZE_AS_BOX: Box<u8> = unsafe { mem::transmute(1337usize) };
+//~^ ERROR it is undefined behavior to use this value
+
+const UNINIT_PTR: *const i32 = unsafe { MaybeUninit { uninit: () }.init };
+//~^ ERROR evaluation of constant value failed
+//~| uninitialized
+
+const NULL_FN_PTR: fn() = unsafe { mem::transmute(0usize) };
+//~^ ERROR it is undefined behavior to use this value
+const UNINIT_FN_PTR: fn() = unsafe { MaybeUninit { uninit: () }.init };
+//~^ ERROR evaluation of constant value failed
+//~| uninitialized
+const DANGLING_FN_PTR: fn() = unsafe { mem::transmute(13usize) };
+//~^ ERROR it is undefined behavior to use this value
+const DATA_FN_PTR: fn() = unsafe { mem::transmute(&13) };
+//~^ ERROR it is undefined behavior to use this value
+
+
+const UNALIGNED_READ: () = unsafe {
+    let x = &[0u8; 4];
+    let ptr = x.as_ptr().cast::<u32>();
+    ptr.read(); //~ inside `UNALIGNED_READ`
+};
+
+
+fn main() {}