error[E0080]: it is undefined behavior to use this value
  --> $DIR/ub-ref.rs:15:1
   |
LL | const UNALIGNED: &u16 = unsafe { mem::transmute(&[0u8; 4]) };
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered unaligned reference
   |
   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior

error[E0080]: it is undefined behavior to use this value
  --> $DIR/ub-ref.rs:18:1
   |
LL | const NULL: &u16 = unsafe { mem::transmute(0usize) };
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered 0, but expected something greater or equal to 1
   |
   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior

error[E0080]: it is undefined behavior to use this value
  --> $DIR/ub-ref.rs:21:1
   |
LL | const REF_AS_USIZE: usize = unsafe { mem::transmute(&0) };
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a pointer, but expected initialized plain bits
   |
   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior

error[E0080]: it is undefined behavior to use this value
  --> $DIR/ub-ref.rs:24:1
   |
LL | const REF_AS_USIZE_SLICE: &[usize] = &[unsafe { mem::transmute(&0) }];
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ a raw memory access tried to access part of a pointer value as raw bytes
   |
   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior

error[E0080]: it is undefined behavior to use this value
  --> $DIR/ub-ref.rs:27:1
   |
LL | const USIZE_AS_REF: &'static u8 = unsafe { mem::transmute(1337usize) };
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered integer pointer in non-ZST reference
   |
   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rust compiler repository if you believe it should not be considered undefined behavior

error: aborting due to 5 previous errors

For more information about this error, try `rustc --explain E0080`.