Rollup merge of #117438 - cjgillot:deterministic-error, r=oli-obk

Do not ICE on constant evaluation failure in GVN. Fixes #117362
rust-lang · Oct 31, 2023 · f623530 · f623530
2 parents 793776f 5b7cc9d
commit f623530
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Showing 4 changed files with 30 additions and 5 deletions.
diff --git a/compiler/rustc_middle/src/mir/consts.rs b/compiler/rustc_middle/src/mir/consts.rs
@@ -520,11 520,13 @@ impl<'tcx> Const<'tcx> {
  // types are fine though.
  ty::ConstKind::Value(_) => c.ty().is_primitive(),
  ty::ConstKind::Unevaluated(..) | ty::ConstKind::Expr(..) => false,
  // This can happen if evaluation of a constant failed. The result does not matter
  // much since compilation is doomed.
  ty::ConstKind::Error(..) => false,
  // Should not appear in runtime MIR.
  ty::ConstKind::Infer(..)
  | ty::ConstKind::Bound(..)
- | ty::ConstKind::Placeholder(..)
- | ty::ConstKind::Error(..) => bug!(),
  | ty::ConstKind::Placeholder(..) => bug!(),
  },
  Const::Unevaluated(..) => false,
  // If the same slice appears twice in the MIR, we cannot guarantee that we will

diff --git a/tests/ui/consts/const-eval/issue-50814-2.mir-opt.stderr b/tests/ui/consts/const-eval/issue-50814-2.mir-opt.stderr
@@ -0,0 1,21 @@
 error[E0080]: evaluation of `<A<()> as Foo<()>>::BAR` failed
  --> $DIR/issue-50814-2.rs:16:24
  |
 LL | const BAR: usize = [5, 6, 7][T::BOO];
  | ^^^^^^^^^^^^^^^^^ index out of bounds: the length is 3 but the index is 42
 
 note: erroneous constant encountered
  --> $DIR/issue-50814-2.rs:20:6
  |
 LL | &<A<T> as Foo<T>>::BAR
  | ^^^^^^^^^^^^^^^^^^^^^
 
 note: erroneous constant encountered
  --> $DIR/issue-50814-2.rs:20:5
  |
 LL | &<A<T> as Foo<T>>::BAR
  | ^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0080`.
diff --git a/...ui/consts/const-eval/issue-50814-2.stderr → ...ts/const-eval/issue-50814-2.normal.stderr b/...ui/consts/const-eval/issue-50814-2.stderr → ...ts/const-eval/issue-50814-2.normal.stderr
@@ -1,17 1,17 @@
 error[E0080]: evaluation of `<A<()> as Foo<()>>::BAR` failed
- --> $DIR/issue-50814-2.rs:14:24
  --> $DIR/issue-50814-2.rs:16:24
  |
 LL | const BAR: usize = [5, 6, 7][T::BOO];
  | ^^^^^^^^^^^^^^^^^ index out of bounds: the length is 3 but the index is 42
 
 note: erroneous constant encountered
- --> $DIR/issue-50814-2.rs:18:6
  --> $DIR/issue-50814-2.rs:20:6
  |
 LL | &<A<T> as Foo<T>>::BAR
  | ^^^^^^^^^^^^^^^^^^^^^
 
 note: the above error was encountered while instantiating `fn foo::<()>`
- --> $DIR/issue-50814-2.rs:30:22
  --> $DIR/issue-50814-2.rs:32:22
  |
 LL | println!("{:x}", foo::<()>() as *const usize as usize);
  | ^^^^^^^^^^^

diff --git a/tests/ui/consts/const-eval/issue-50814-2.rs b/tests/ui/consts/const-eval/issue-50814-2.rs
@@ -1,4 1,6 @@
 // build-fail
 // revisions: normal mir-opt
 // [mir-opt]compile-flags: -Zmir-opt-level=4
 
 trait C {
  const BOO: usize;