Rollup merge of #92432 - fee1-dead:constck-impl-constness, r=oli-obk

Error when selected impl is not const in constck

Catches bad things when checking a `default_method_body_is_const` body, such as:

```rust
self.map(/* .. */).is_sorted();
```

When `Map` does not yet have a `const` `impl` for `Iterator`.

r? ```@oli-obk```

1 files changed, 5 insertions, 1 deletions

diff --git a/compiler/rustc_const_eval/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
index dd749c03934..de4824eb667 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
@@ -810,7 +810,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                         param_env,
                         Binder::dummy(TraitPredicate {
                             trait_ref,
-                            constness: ty::BoundConstness::ConstIfConst,
+                            constness: ty::BoundConstness::NotConst,
                             polarity: ty::ImplPolarity::Positive,
                         }),
                     );
@@ -829,6 +829,10 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                             return;
                         }
                         Ok(Some(ImplSource::UserDefined(data))) => {
+                            if let hir::Constness::NotConst = tcx.impl_constness(data.impl_def_id) {
+                                self.check_op(ops::FnCallNonConst(None));
+                                return;
+                            }
                             let callee_name = tcx.item_name(callee);
                             if let Some(&did) = tcx
                                 .associated_item_def_ids(data.impl_def_id)