Auto merge of #92518 - matthiaskrgr:rollup-fl8z4e7, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #90102 (Remove `NullOp::Box`)
 - #92011 (Use field span in `rustc_macros` when emitting decode call)
 - #92402 (Suggest while let x = y when encountering while x = y)
 - #92409 (Couple of libtest cleanups)
 - #92418 (Fix spacing in pretty printed PatKind::Struct with no fields)
 - #92444 (Consolidate Result's and Option's methods into fewer impl blocks)

Failed merges:

 - #92483 (Stabilize `result_cloned` and `result_copied`)

r? `@ghost`
`@rustbot` modify labels: rollup

3 files changed, 1 insertions, 12 deletions

diff --git a/compiler/rustc_const_eval/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs
index 246807a112a..0fc3827d16c 100644
--- a/compiler/rustc_const_eval/src/interpret/eval_context.rs
+++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs
@@ -156,7 +156,7 @@ pub enum StackPopCleanup {
     /// `ret` stores the block we jump to on a normal return, while `unwind`
     /// stores the block used for cleanup during unwinding.
     Goto { ret: Option<mir::BasicBlock>, unwind: StackPopUnwind },
-    /// Just do nothing: Used by Main and for the `box_alloc` hook in miri.
+    /// Just do nothing: Used by Main and for TLS hooks in miri.
     /// `cleanup` says whether locals are deallocated. Static computation
     /// wants them leaked to intern what they need (and just throw away
     /// the entire `ecx` when it is done).
diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs
index 6a03b699d47..23ec3875cbc 100644
--- a/compiler/rustc_const_eval/src/interpret/machine.rs
+++ b/compiler/rustc_const_eval/src/interpret/machine.rs
@@ -212,12 +212,6 @@ pub trait Machine<'mir, 'tcx>: Sized {
         right: &ImmTy<'tcx, Self::PointerTag>,
     ) -> InterpResult<'tcx, (Scalar<Self::PointerTag>, bool, Ty<'tcx>)>;
 
-    /// Heap allocations via the `box` keyword.
-    fn box_alloc(
-        ecx: &mut InterpCx<'mir, 'tcx, Self>,
-        dest: &PlaceTy<'tcx, Self::PointerTag>,
-    ) -> InterpResult<'tcx>;
-
     /// Called to read the specified `local` from the `frame`.
     /// Since reading a ZST is not actually accessing memory or locals, this is never invoked
     /// for ZST reads.
diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs
index 6e37aae0f5e..3daa1d3c2b3 100644
--- a/compiler/rustc_const_eval/src/interpret/step.rs
+++ b/compiler/rustc_const_eval/src/interpret/step.rs
@@ -271,10 +271,6 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 self.write_immediate(place.to_ref(self), &dest)?;
             }
 
-            NullaryOp(mir::NullOp::Box, _) => {
-                M::box_alloc(self, &dest)?;
-            }
-
             NullaryOp(null_op, ty) => {
                 let ty = self.subst_from_current_frame_and_normalize_erasing_regions(ty)?;
                 let layout = self.layout_of(ty)?;
@@ -289,7 +285,6 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let val = match null_op {
                     mir::NullOp::SizeOf => layout.size.bytes(),
                     mir::NullOp::AlignOf => layout.align.abi.bytes(),
-                    mir::NullOp::Box => unreachable!(),
                 };
                 self.write_scalar(Scalar::from_machine_usize(val, self), &dest)?;
             }