From 2192d869d0624a2013e45183db1cf3595aa7d989 Mon Sep 17 00:00:00 2001
From: Scott McMurray <scottmcm@users.noreply.github.com>
Date: Wed, 4 Jun 2025 01:44:40 -0700
Subject: [PATCH] Update `InterpCx::project_field` to take `FieldIdx`

As suggested by Ralf in 142005.
---
 src/inline_asm.rs | 2 +-
 src/vtable.rs     | 5 ++---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/inline_asm.rs b/src/inline_asm.rs
index afee50955497..120d6ff9e38e 100644
--- a/src/inline_asm.rs
+++ b/src/inline_asm.rs
@@ -850,7 +850,7 @@ fn asm_clif_type<'tcx>(fx: &FunctionCx<'_, '_, 'tcx>, ty: Ty<'tcx>) -> Option<ty
         // Adapted from https://github.com/rust-lang/rust/blob/f3c66088610c1b80110297c2d9a8b5f9265b013f/compiler/rustc_hir_analysis/src/check/intrinsicck.rs#L136-L151
         ty::Adt(adt, args) if fx.tcx.is_lang_item(adt.did(), LangItem::MaybeUninit) => {
             let fields = &adt.non_enum_variant().fields;
-            let ty = fields[FieldIdx::from_u32(1)].ty(fx.tcx, args);
+            let ty = fields[FieldIdx::ONE].ty(fx.tcx, args);
             let ty::Adt(ty, args) = ty.kind() else {
                 unreachable!("expected first field of `MaybeUninit` to be an ADT")
             };
diff --git a/src/vtable.rs b/src/vtable.rs
index 9d9e0462a9b7..05a8e3c33421 100644
--- a/src/vtable.rs
+++ b/src/vtable.rs
@@ -53,7 +53,7 @@ pub(crate) fn get_ptr_and_method_ref<'tcx>(
                     .layout()
                     .non_1zst_field(fx)
                     .expect("not exactly one non-1-ZST field in a `DispatchFromDyn` type");
-                arg = arg.value_field(fx, FieldIdx::new(idx));
+                arg = arg.value_field(fx, idx);
             }
         }
 
@@ -62,8 +62,7 @@ pub(crate) fn get_ptr_and_method_ref<'tcx>(
                 let inner_layout = fx.layout_of(arg.layout().ty.builtin_deref(true).unwrap());
                 let dyn_star = CPlace::for_ptr(Pointer::new(arg.load_scalar(fx)), inner_layout);
                 let ptr = dyn_star.place_field(fx, FieldIdx::ZERO).to_ptr();
-                let vtable =
-                    dyn_star.place_field(fx, FieldIdx::new(1)).to_cvalue(fx).load_scalar(fx);
+                let vtable = dyn_star.place_field(fx, FieldIdx::ONE).to_cvalue(fx).load_scalar(fx);
                 break 'block (ptr, vtable);
             }
         }