make it more clear what comments refer to; avoid dangling unaligned r…

…eferences Co-authored-by: Waffle Maybe <[email protected]>
rust-lang · Dec 12, 2023 · df227f7 · df227f7
1 parent b9c9b3e
commit df227f7
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Showing 2 changed files with 11 additions and 5 deletions.
diff --git a/tests/ui/consts/const-eval/issue-91827-extern-types-field-offset.rs b/tests/ui/consts/const-eval/issue-91827-extern-types-field-offset.rs
@@ -17,15 17,21 @@ struct S {
 }
 
 const NEWTYPE: () = unsafe {
  let buf = [0i32; 4];
  let x: &Newtype = &*(&buf as *const _ as *const Newtype);
 
  // Projecting to the newtype works, because it is always at offset 0.
- let x: &Newtype = unsafe { &*(1usize as *const Newtype) };
  let field = &x.0;
 };
 
 const OFFSET: () = unsafe {
- // This needs to compute the field offset, but we don't know the type's alignment, so this fail.
- let x: &S = unsafe { &*(1usize as *const S) };
- let field = &x.a; //~ERROR: evaluation of constant value failed
  let buf = [0i32; 4];
  let x: &S = &*(&buf as *const _ as *const S);
 
  // This needs to compute the field offset, but we don't know the type's alignment, so this
  // fails.
  let field = &x.a;
  //~^ ERROR: evaluation of constant value failed
  //~| does not have a known offset
 };
 

diff --git a/tests/ui/consts/const-eval/issue-91827-extern-types-field-offset.stderr b/tests/ui/consts/const-eval/issue-91827-extern-types-field-offset.stderr
@@ -1,5 1,5 @@
 error[E0080]: evaluation of constant value failed
- --> $DIR/issue-91827-extern-types-field-offset.rs:28:17
  --> $DIR/issue-91827-extern-types-field-offset.rs:33:17
  |
 LL | let field = &x.a;
  | ^^^^ `extern type` does not have a known offset