diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index 16472c787572c..e68a6f52c73a2 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -821,9 +821,6 @@ pub struct LocalDecl<'tcx> {
/// flag drop flags to avoid triggering this check as they are introduced
/// after typeck.
///
- /// Unsafety checking will also ignore dereferences of these locals,
- /// so they can be used for raw pointers only used in a desugaring.
- ///
/// This should be sound because the drop flags are fully algebraic, and
/// therefore don't affect the OIBIT or outlives properties of the
/// generator.
@@ -1010,13 +1007,13 @@ impl<'tcx> LocalDecl<'tcx> {
}
/// Returns `Some` if this is a reference to a static item that is used to
- /// access that static
+ /// access that static.
pub fn is_ref_to_static(&self) -> bool {
matches!(self.local_info, Some(box LocalInfo::StaticRef { .. }))
}
- /// Returns `Some` if this is a reference to a static item that is used to
- /// access that static
+ /// Returns `Some` if this is a reference to a thread-local static item that is used to
+ /// access that static.
pub fn is_ref_to_thread_local(&self) -> bool {
match self.local_info {
Some(box LocalInfo::StaticRef { is_thread_local, .. }) => is_thread_local,
diff --git a/compiler/rustc_middle/src/mir/tcx.rs b/compiler/rustc_middle/src/mir/tcx.rs
index b9e4f6fb12eb1..f0bfdae261c64 100644
--- a/compiler/rustc_middle/src/mir/tcx.rs
+++ b/compiler/rustc_middle/src/mir/tcx.rs
@@ -152,10 +152,14 @@ impl<'tcx> Rvalue<'tcx> {
tcx.mk_ty(ty::Array(operand.ty(local_decls, tcx), count))
}
Rvalue::ThreadLocalRef(did) => {
+ let static_ty = tcx.type_of(did);
if tcx.is_mutable_static(did) {
- tcx.mk_mut_ptr(tcx.type_of(did))
+ tcx.mk_mut_ptr(static_ty)
+ } else if tcx.is_foreign_item(did) {
+ tcx.mk_imm_ptr(static_ty)
} else {
- tcx.mk_imm_ref(tcx.lifetimes.re_static, tcx.type_of(did))
+ // FIXME: These things don't *really* have 'static lifetime.
+ tcx.mk_imm_ref(tcx.lifetimes.re_static, static_ty)
}
}
Rvalue::Ref(reg, bk, ref place) => {
diff --git a/compiler/rustc_middle/src/ty/util.rs b/compiler/rustc_middle/src/ty/util.rs
index b0f0f0ba57fad..4a20e1c32f99e 100644
--- a/compiler/rustc_middle/src/ty/util.rs
+++ b/compiler/rustc_middle/src/ty/util.rs
@@ -529,8 +529,12 @@ impl<'tcx> TyCtxt<'tcx> {
// Make sure that any constants in the static's type are evaluated.
let static_ty = self.normalize_erasing_regions(ty::ParamEnv::empty(), self.type_of(def_id));
+ // Make sure that accesses to unsafe statics end up using raw pointers.
+ // For thread-locals, this needs to be kept in sync with `Rvalue::ty`.
if self.is_mutable_static(def_id) {
self.mk_mut_ptr(static_ty)
+ } else if self.is_foreign_item(def_id) {
+ self.mk_imm_ptr(static_ty)
} else {
self.mk_imm_ref(self.lifetimes.re_erased, static_ty)
}
diff --git a/compiler/rustc_mir/src/transform/check_unsafety.rs b/compiler/rustc_mir/src/transform/check_unsafety.rs
index 7309a4129e468..3d68b862df2d0 100644
--- a/compiler/rustc_mir/src/transform/check_unsafety.rs
+++ b/compiler/rustc_mir/src/transform/check_unsafety.rs
@@ -204,6 +204,9 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
if let [] = proj_base {
let decl = &self.body.local_decls[place.local];
if decl.internal {
+ // If the projection root is an artifical local that we introduced when
+ // desugaring `static`, give a more specific error message
+ // (avoid the general "raw pointer" clause below, that would only be confusing).
if let Some(box LocalInfo::StaticRef { def_id, .. }) = decl.local_info {
if self.tcx.is_mutable_static(def_id) {
self.require_unsafe(
diff --git a/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].ConstProp.after.mir b/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].ConstProp.after.mir
index 0d5760b4cd5c7..88d583b815adb 100644
--- a/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].ConstProp.after.mir
+++ b/src/test/mir-opt/const_promotion_extern_static.FOO-promoted[0].ConstProp.after.mir
@@ -4,17 +4,17 @@ promoted[0] in FOO: &[&i32; 1] = {
let mut _0: &[&i32; 1]; // return place in scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
let mut _1: [&i32; 1]; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
let mut _2: &i32; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:32: 13:45
- let mut _3: &i32; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
+ let mut _3: *const i32; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
bb0: {
- _3 = const {alloc2: &i32}; // scope 0 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
+ _3 = const {alloc2: *const i32}; // scope 0 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
// ty::Const
- // + ty: &i32
+ // + ty: *const i32
// + val: Value(Scalar(alloc2))
// mir::Constant
// + span: $DIR/const-promotion-extern-static.rs:13:42: 13:43
- // + literal: Const { ty: &i32, val: Value(Scalar(alloc2)) }
- _2 = _3; // scope 0 at $DIR/const-promotion-extern-static.rs:13:41: 13:43
+ // + literal: Const { ty: *const i32, val: Value(Scalar(alloc2)) }
+ _2 = &(*_3); // scope 0 at $DIR/const-promotion-extern-static.rs:13:41: 13:43
_1 = [move _2]; // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
_0 = &_1; // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
return; // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
diff --git a/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff b/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff
index a392334e0c955..82277b2a21cbe 100644
--- a/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff
+++ b/src/test/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff
@@ -7,7 +7,7 @@
let mut _2: &[&i32; 1]; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
let _3: [&i32; 1]; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
let mut _4: &i32; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:32: 13:45
- let _5: &i32; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
+ let _5: *const i32; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
+ let mut _6: &[&i32; 1]; // in scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
scope 1 {
}
@@ -18,16 +18,16 @@
- StorageLive(_3); // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
- StorageLive(_4); // scope 0 at $DIR/const-promotion-extern-static.rs:13:32: 13:45
- StorageLive(_5); // scope 1 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
-- _5 = const {alloc2: &i32}; // scope 1 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
+- _5 = const {alloc2: *const i32}; // scope 1 at $DIR/const-promotion-extern-static.rs:13:42: 13:43
+ _6 = const FOO::promoted[0]; // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
// ty::Const
-- // + ty: &i32
+- // + ty: *const i32
- // + val: Value(Scalar(alloc2))
+ // + ty: &[&i32; 1]
+ // + val: Unevaluated(WithOptConstParam { did: DefId(0:7 ~ const_promotion_extern_static[317d]::FOO), const_param_did: None }, [], Some(promoted[0]))
// mir::Constant
- // + span: $DIR/const-promotion-extern-static.rs:13:42: 13:43
-- // + literal: Const { ty: &i32, val: Value(Scalar(alloc2)) }
+- // + literal: Const { ty: *const i32, val: Value(Scalar(alloc2)) }
- _4 = &(*_5); // scope 1 at $DIR/const-promotion-extern-static.rs:13:41: 13:43
- _3 = [move _4]; // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46
- _2 = &_3; // scope 0 at $DIR/const-promotion-extern-static.rs:13:31: 13:46