From 6210c26a5adcf9d9d469ef8c9820d937c42dc1e4 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 8 Jun 2024 11:26:56 +0200
Subject: [PATCH] offset_of: allow (unstably) taking the offset of slice tail
 fields

---
 src/base.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/base.rs b/src/base.rs
index 963e5de91ce..6d26ca0b899 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -832,9 +832,10 @@ fn codegen_stmt<'tcx>(
                     let val = match null_op {
                         NullOp::SizeOf => layout.size.bytes(),
                         NullOp::AlignOf => layout.align.abi.bytes(),
-                        NullOp::OffsetOf(fields) => {
-                            layout.offset_of_subfield(fx, fields.iter()).bytes()
-                        }
+                        NullOp::OffsetOf(fields) => fx
+                            .tcx
+                            .offset_of_subfield(ParamEnv::reveal_all(), layout, fields.iter())
+                            .bytes(),
                         NullOp::UbChecks => {
                             let val = fx.tcx.sess.ub_checks();
                             let val = CValue::by_val(