Revert "Auto merge of #133734 - scottmcm:lower-indexing-to-ptrmetadata, r=davidtwco,RalfJung"

This reverts commit b57d93d8b9525fa261404b4cd9c0670eeb1264b8, reversing
changes made to 0aeaa5eb22180fdf12a8489e63c4daa18da6f236.

1 files changed, 8 insertions, 0 deletions

diff --git a/compiler/rustc_mir_transform/src/validate.rs b/compiler/rustc_mir_transform/src/validate.rs
index 42154bbf7f2..b62e34ac08d 100644
--- a/compiler/rustc_mir_transform/src/validate.rs
+++ b/compiler/rustc_mir_transform/src/validate.rs
@@ -1124,6 +1124,14 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                         );
                     }
                     UnOp::PtrMetadata => {
+                        if !matches!(self.body.phase, MirPhase::Runtime(_)) {
+                            // It would probably be fine to support this in earlier phases, but at
+                            // the time of writing it's only ever introduced from intrinsic
+                            // lowering or other runtime-phase optimization passes, so earlier
+                            // things can just `bug!` on it.
+                            self.fail(location, "PtrMetadata should be in runtime MIR only");
+                        }
+
                         check_kinds!(
                             a,
                             "Cannot PtrMetadata non-pointer non-reference type {:?}",