Rollup merge of #116522 - bvanjoi:fix-115599, r=oli-obk

use `PatKind::Error` when an ADT const value has violation

Fixes #115599

Since the [to_pat](https://github.com/rust-lang/rust/pull/111913/files#diff-6d8d99538aca600d633270051580c7a9e40b35824ea2863d9dda2c85a733b5d9R126-R155) behavior has been changed in the #111913 update, the kind of `inlined_const_ast_pat` has transformed from `PatKind::Leaf { pattern: Pat { kind: Wild, ..} } ` to `PatKind::Constant`. This caused a scenario where there are no matched candidates, leading to a testing of the candidates. This process ultimately attempts to test the string const, triggering the `bug!` invocation finally.

r? ``@oli-obk``

1 files changed, 8 insertions, 0 deletions

diff --git a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
index b7818fe57d1..fc03f7891a8 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
@@ -198,6 +198,14 @@ impl<'tcx> ConstToPat<'tcx> {
                     // We errored. Signal that in the pattern, so that follow up errors can be silenced.
                     let kind = PatKind::Error(e);
                     return Box::new(Pat { span: self.span, ty: cv.ty(), kind });
+                } else if let ty::Adt(..) = cv.ty().kind() && matches!(cv, mir::Const::Val(..)) {
+                    // This branch is only entered when the current `cv` is `mir::Const::Val`.
+                    // This is because `mir::Const::ty` has already been handled by `Self::recur`
+                    // and the invalid types may be ignored.
+                    let err = TypeNotStructural { span: self.span, non_sm_ty };
+                    let e = self.tcx().sess.emit_err(err);
+                    let kind = PatKind::Error(e);
+                    return Box::new(Pat { span: self.span, ty: cv.ty(), kind });
                 } else if !self.saw_const_match_lint.get() {
                     if let Some(mir_structural_match_violation) = mir_structural_match_violation {
                         match non_sm_ty.kind() {