The mutability was ignored anyway, so just check for staticness

Author: oli-obk

compiler/rustc_const_eval/src/const_eval/eval_queries.rs

@@ -335,13 +335,16 @@ pub fn eval_to_allocation_raw_provider<'tcx>(
                 let mut ref_tracking = RefTracking::new(mplace.clone());
                 let mut inner = false;
                 while let Some((mplace, path)) = ref_tracking.todo.pop() {
-                    let mode = match tcx.static_mutability(cid.instance.def_id()) {
-                        Some(_) if cid.promoted.is_some() => {
+                    let mode = if is_static {
+                        if cid.promoted.is_some() {
                             // Promoteds in statics are allowed to point to statics.
                             CtfeValidationMode::Const { inner, allow_static_ptrs: true }
+                        } else {
+                            // a `static`
+                            CtfeValidationMode::Regular
                         }
-                        Some(_) => CtfeValidationMode::Regular, // a `static`
-                        None => CtfeValidationMode::Const { inner, allow_static_ptrs: false },
+                    } else {
+                        CtfeValidationMode::Const { inner, allow_static_ptrs: false }
                     };
                     ecx.const_validate_operand(&mplace.into(), path, &mut ref_tracking, mode)?;
                     inner = true;