diff --git a/compiler/rustc_const_eval/src/transform/validate.rs b/compiler/rustc_const_eval/src/transform/validate.rs
index bb897b95b2c53..94e1b95a0eb3c 100644
--- a/compiler/rustc_const_eval/src/transform/validate.rs
+++ b/compiler/rustc_const_eval/src/transform/validate.rs
@@ -9,8 +9,8 @@ use rustc_middle::mir::visit::{PlaceContext, Visitor};
use rustc_middle::mir::{
traversal, AggregateKind, BasicBlock, BinOp, Body, BorrowKind, CastKind, CopyNonOverlapping,
Local, Location, MirPass, MirPhase, NonDivergingIntrinsic, Operand, Place, PlaceElem, PlaceRef,
- ProjectionElem, RuntimePhase, Rvalue, SourceScope, Statement, StatementKind, Terminator,
- TerminatorKind, UnOp, START_BLOCK,
+ ProjectionElem, RetagKind, RuntimePhase, Rvalue, SourceScope, Statement, StatementKind,
+ Terminator, TerminatorKind, UnOp, START_BLOCK,
};
use rustc_middle::ty::{self, InstanceDef, ParamEnv, Ty, TyCtxt, TypeVisitable};
use rustc_mir_dataflow::impls::MaybeStorageLive;
@@ -667,10 +667,13 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
self.fail(location, "`Deinit`is not allowed until deaggregation");
}
}
- StatementKind::Retag(_, _) => {
+ StatementKind::Retag(kind, _) => {
// FIXME(JakobDegen) The validator should check that `self.mir_phase <
// DropsLowered`. However, this causes ICEs with generation of drop shims, which
// seem to fail to set their `MirPhase` correctly.
+ if *kind == RetagKind::Raw || *kind == RetagKind::TwoPhase {
+ self.fail(location, format!("explicit `{:?}` is forbidden", kind));
+ }
}
StatementKind::StorageLive(..)
| StatementKind::StorageDead(..)
diff --git a/compiler/rustc_middle/src/mir/syntax.rs b/compiler/rustc_middle/src/mir/syntax.rs
index 99e59c770d754..bb03359b138f3 100644
--- a/compiler/rustc_middle/src/mir/syntax.rs
+++ b/compiler/rustc_middle/src/mir/syntax.rs
@@ -320,8 +320,10 @@ pub enum StatementKind<'tcx> {
/// for
/// more details.
///
- /// For code that is not specific to stacked borrows, you should consider retags to read
- /// and modify the place in an opaque way.
+ /// For code that is not specific to stacked borrows, you should consider retags to read and
+ /// modify the place in an opaque way.
+ ///
+ /// Only `RetagKind::Default` and `RetagKind::FnEntry` are permitted.
Retag(RetagKind, Box>),
/// Encodes a user's type ascription. These need to be preserved
diff --git a/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs b/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs
index 7c39a93a8eb9e..dca4906c07de5 100644
--- a/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs
+++ b/compiler/rustc_mir_build/src/build/custom/parse/instruction.rs
@@ -15,9 +15,6 @@ impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
@call("mir_retag", args) => {
Ok(StatementKind::Retag(RetagKind::Default, Box::new(self.parse_place(args[0])?)))
},
- @call("mir_retag_raw", args) => {
- Ok(StatementKind::Retag(RetagKind::Raw, Box::new(self.parse_place(args[0])?)))
- },
@call("mir_set_discriminant", args) => {
let place = self.parse_place(args[0])?;
let var = self.parse_integer_literal(args[1])? as u32;
diff --git a/library/core/src/intrinsics/mir.rs b/library/core/src/intrinsics/mir.rs
index e08a15571fcbe..9e7099ddfd1e1 100644
--- a/library/core/src/intrinsics/mir.rs
+++ b/library/core/src/intrinsics/mir.rs
@@ -259,7 +259,6 @@ define!("mir_drop", fn Drop(place: T, goto: BasicBlock));
define!("mir_drop_and_replace", fn DropAndReplace(place: T, value: T, goto: BasicBlock));
define!("mir_call", fn Call(place: T, goto: BasicBlock, call: T));
define!("mir_retag", fn Retag(place: T));
-define!("mir_retag_raw", fn RetagRaw(place: T));
define!("mir_move", fn Move(place: T) -> T);
define!("mir_static", fn Static(s: T) -> &'static T);
define!("mir_static_mut", fn StaticMut(s: T) -> *mut T);
diff --git a/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir b/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir
index 4d38d45c0f479..f5ee112623541 100644
--- a/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir
+++ b/src/test/mir-opt/building/custom/references.immut_ref.built.after.mir
@@ -6,9 +6,8 @@ fn immut_ref(_1: &i32) -> &i32 {
bb0: {
_2 = &raw const (*_1); // scope 0 at $DIR/references.rs:+5:13: +5:29
- Retag([raw] _2); // scope 0 at $DIR/references.rs:+6:13: +6:24
- _0 = &(*_2); // scope 0 at $DIR/references.rs:+7:13: +7:23
- Retag(_0); // scope 0 at $DIR/references.rs:+8:13: +8:23
- return; // scope 0 at $DIR/references.rs:+9:13: +9:21
+ _0 = &(*_2); // scope 0 at $DIR/references.rs:+6:13: +6:23
+ Retag(_0); // scope 0 at $DIR/references.rs:+7:13: +7:23
+ return; // scope 0 at $DIR/references.rs:+8:13: +8:21
}
}
diff --git a/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir b/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir
index 01bc8a9cd3580..8e2ffc33b1a0a 100644
--- a/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir
+++ b/src/test/mir-opt/building/custom/references.mut_ref.built.after.mir
@@ -6,9 +6,8 @@ fn mut_ref(_1: &mut i32) -> &mut i32 {
bb0: {
_2 = &raw mut (*_1); // scope 0 at $DIR/references.rs:+5:13: +5:33
- Retag([raw] _2); // scope 0 at $DIR/references.rs:+6:13: +6:24
- _0 = &mut (*_2); // scope 0 at $DIR/references.rs:+7:13: +7:26
- Retag(_0); // scope 0 at $DIR/references.rs:+8:13: +8:23
- return; // scope 0 at $DIR/references.rs:+9:13: +9:21
+ _0 = &mut (*_2); // scope 0 at $DIR/references.rs:+6:13: +6:26
+ Retag(_0); // scope 0 at $DIR/references.rs:+7:13: +7:23
+ return; // scope 0 at $DIR/references.rs:+8:13: +8:21
}
}
diff --git a/src/test/mir-opt/building/custom/references.rs b/src/test/mir-opt/building/custom/references.rs
index c93f6ec624b35..a1c896de04cf0 100644
--- a/src/test/mir-opt/building/custom/references.rs
+++ b/src/test/mir-opt/building/custom/references.rs
@@ -12,7 +12,6 @@ pub fn mut_ref(x: &mut i32) -> &mut i32 {
{
t = addr_of_mut!(*x);
- RetagRaw(t);
RET = &mut *t;
Retag(RET);
Return()
@@ -28,7 +27,6 @@ pub fn immut_ref(x: &i32) -> &i32 {
{
t = addr_of!(*x);
- RetagRaw(t);
RET = & *t;
Retag(RET);
Return()