From 8b2a7da3b0d5ef813c3ecbdde2a550eedef27712 Mon Sep 17 00:00:00 2001
From: Nilstrieb <48135649+Nilstrieb@users.noreply.github.com>
Date: Mon, 12 Dec 2022 15:47:32 +0100
Subject: [PATCH 1/2] Rename `assert_uninit_valid` intrinsic
It's not about "uninit" anymore but about "filling with 0x01 bytes" so
the name should at least try to reflect that.
---
compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs | 6 ++++--
compiler/rustc_codegen_ssa/src/mir/block.rs | 6 +++---
compiler/rustc_const_eval/src/interpret/intrinsics.rs | 6 ++++--
compiler/rustc_hir_analysis/src/check/intrinsic.rs | 8 ++++----
compiler/rustc_span/src/symbol.rs | 2 +-
library/core/src/intrinsics.rs | 7 ++++---
library/core/src/mem/mod.rs | 3 ++-
src/test/ui/consts/assert-type-intrinsics.rs | 2 +-
src/test/ui/consts/assert-type-intrinsics.stderr | 4 ++--
9 files changed, 25 insertions(+), 19 deletions(-)
diff --git a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
index 0302b843aa226..e4a27f1bb6d40 100644
--- a/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
+++ b/compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
@@ -713,7 +713,7 @@ fn codegen_regular_intrinsic_call<'tcx>(
let res = CValue::by_val(swap(&mut fx.bcx, val), arg.layout());
ret.write_cvalue(fx, res);
}
- sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
+ sym::assert_inhabited | sym::assert_zero_valid | sym::assert_mem_uninitialized_valid => {
intrinsic_args!(fx, args => (); intrinsic);
let layout = fx.layout_of(substs.type_at(0));
@@ -742,7 +742,9 @@ fn codegen_regular_intrinsic_call<'tcx>(
return;
}
- if intrinsic == sym::assert_uninit_valid && !fx.tcx.permits_uninit_init(layout) {
+ if intrinsic == sym::assert_mem_uninitialized_valid
+ && !fx.tcx.permits_uninit_init(layout)
+ {
with_no_trimmed_paths!({
crate::base::codegen_panic(
fx,
diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs
index f3f5ddb52d6a4..a1cd43f749ec0 100644
--- a/compiler/rustc_codegen_ssa/src/mir/block.rs
+++ b/compiler/rustc_codegen_ssa/src/mir/block.rs
@@ -666,12 +666,12 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
enum AssertIntrinsic {
Inhabited,
ZeroValid,
- UninitValid,
+ MemUninitializedValid,
}
let panic_intrinsic = intrinsic.and_then(|i| match i {
sym::assert_inhabited => Some(AssertIntrinsic::Inhabited),
sym::assert_zero_valid => Some(AssertIntrinsic::ZeroValid),
- sym::assert_uninit_valid => Some(AssertIntrinsic::UninitValid),
+ sym::assert_mem_uninitialized_valid => Some(AssertIntrinsic::MemUninitializedValid),
_ => None,
});
if let Some(intrinsic) = panic_intrinsic {
@@ -682,7 +682,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
let do_panic = match intrinsic {
Inhabited => layout.abi.is_uninhabited(),
ZeroValid => !bx.tcx().permits_zero_init(layout),
- UninitValid => !bx.tcx().permits_uninit_init(layout),
+ MemUninitializedValid => !bx.tcx().permits_uninit_init(layout),
};
Some(if do_panic {
let msg_str = with_no_visible_paths!({
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index 7940efcd2b11f..27abc2b97b028 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -432,7 +432,9 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
sym::transmute => {
self.copy_op(&args[0], dest, /*allow_transmute*/ true)?;
}
- sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
+ sym::assert_inhabited
+ | sym::assert_zero_valid
+ | sym::assert_mem_uninitialized_valid => {
let ty = instance.substs.type_at(0);
let layout = self.layout_of(ty)?;
@@ -464,7 +466,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
}
}
- if intrinsic_name == sym::assert_uninit_valid {
+ if intrinsic_name == sym::assert_mem_uninitialized_valid {
let should_panic = !self.tcx.permits_uninit_init(layout);
if should_panic {
diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
index 69e54b41d4c04..598dc2dca5c62 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
@@ -75,7 +75,7 @@ pub fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: DefId) -> hir
sym::abort
| sym::assert_inhabited
| sym::assert_zero_valid
- | sym::assert_uninit_valid
+ | sym::assert_mem_uninitialized_valid
| sym::size_of
| sym::min_align_of
| sym::needs_drop
@@ -193,9 +193,9 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
}
sym::rustc_peek => (1, vec![param(0)], param(0)),
sym::caller_location => (0, vec![], tcx.caller_location_ty()),
- sym::assert_inhabited | sym::assert_zero_valid | sym::assert_uninit_valid => {
- (1, Vec::new(), tcx.mk_unit())
- }
+ sym::assert_inhabited
+ | sym::assert_zero_valid
+ | sym::assert_mem_uninitialized_valid => (1, Vec::new(), tcx.mk_unit()),
sym::forget => (1, vec![param(0)], tcx.mk_unit()),
sym::transmute => (2, vec![param(0)], param(1)),
sym::prefetch_read_data
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 1fcf8c7a8bf13..c97340983c010 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -377,9 +377,9 @@ symbols! {
assert_eq_macro,
assert_inhabited,
assert_macro,
+ assert_mem_uninitialized_valid,
assert_ne_macro,
assert_receiver_is_total_eq,
- assert_uninit_valid,
assert_zero_valid,
asserting,
associated_const_equality,
diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs
index 7ed7d767f2fb5..ed58a7f179935 100644
--- a/library/core/src/intrinsics.rs
+++ b/library/core/src/intrinsics.rs
@@ -959,13 +959,14 @@ extern "rust-intrinsic" {
#[rustc_safe_intrinsic]
pub fn assert_zero_valid<T>();
- /// A guard for unsafe functions that cannot ever be executed if `T` has invalid
- /// bit patterns: This will statically either panic, or do nothing.
+ /// A guard for `std::mem::uninitialized`. Checks whether a repeated bit pattern `0x01`
+ /// is legal for `T`: This will statically either panic, or do nothing.
///
/// This intrinsic does not have a stable counterpart.
#[rustc_const_unstable(feature = "const_assert_type2", issue = "none")]
#[rustc_safe_intrinsic]
- pub fn assert_uninit_valid<T>();
+ #[cfg(not(bootstrap))]
+ pub fn assert_mem_uninitialized_valid<T>();
/// Gets a reference to a static `Location` indicating where it was called.
///
diff --git a/library/core/src/mem/mod.rs b/library/core/src/mem/mod.rs
index 383bdc7b6e2e9..5e01ccc07d8fd 100644
--- a/library/core/src/mem/mod.rs
+++ b/library/core/src/mem/mod.rs
@@ -682,7 +682,8 @@ pub unsafe fn zeroed<T>() -> T {
pub unsafe fn uninitialized<T>() -> T {
// SAFETY: the caller must guarantee that an uninitialized value is valid for `T`.
unsafe {
- intrinsics::assert_uninit_valid::<T>();
+ #[cfg(not(bootstrap))] // If the compiler hits this itself then it deserves the UB.
+ intrinsics::assert_mem_uninitialized_valid::<T>();
let mut val = MaybeUninit::<T>::uninit();
// Fill memory with 0x01, as an imperfect mitigation for old code that uses this function on
diff --git a/src/test/ui/consts/assert-type-intrinsics.rs b/src/test/ui/consts/assert-type-intrinsics.rs
index 263d1ae6a3ec7..b4fd423becd9d 100644
--- a/src/test/ui/consts/assert-type-intrinsics.rs
+++ b/src/test/ui/consts/assert-type-intrinsics.rs
@@ -13,7 +13,7 @@ fn main() {
//~^ERROR: evaluation of constant value failed
};
const _BAD2: () = {
- intrinsics::assert_uninit_valid::<&'static i32>();
+ intrinsics::assert_mem_uninitialized_valid::<&'static i32>();
//~^ERROR: evaluation of constant value failed
};
const _BAD3: () = {
diff --git a/src/test/ui/consts/assert-type-intrinsics.stderr b/src/test/ui/consts/assert-type-intrinsics.stderr
index f92f9fda069ad..70aec91e22622 100644
--- a/src/test/ui/consts/assert-type-intrinsics.stderr
+++ b/src/test/ui/consts/assert-type-intrinsics.stderr
@@ -7,8 +7,8 @@ LL | MaybeUninit::<!>::uninit().assume_init();
error[E0080]: evaluation of constant value failed
--> $DIR/assert-type-intrinsics.rs:16:9
|
-LL | intrinsics::assert_uninit_valid::<&'static i32>();
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ aborted execution: attempted to leave type `&i32` uninitialized, which is invalid
+LL | intrinsics::assert_mem_uninitialized_valid::<&'static i32>();
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ aborted execution: attempted to leave type `&i32` uninitialized, which is invalid
error[E0080]: evaluation of constant value failed
--> $DIR/assert-type-intrinsics.rs:20:9
From 6f21ba4a06b7fa17113b7029c4aa7805db16aa32 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Wed, 21 Dec 2022 11:06:20 +0100
Subject: [PATCH 2/2] less specific wording
---
library/core/src/intrinsics.rs | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs
index ed58a7f179935..a521905a9e735 100644
--- a/library/core/src/intrinsics.rs
+++ b/library/core/src/intrinsics.rs
@@ -959,8 +959,7 @@ extern "rust-intrinsic" {
#[rustc_safe_intrinsic]
pub fn assert_zero_valid<T>();
- /// A guard for `std::mem::uninitialized`. Checks whether a repeated bit pattern `0x01`
- /// is legal for `T`: This will statically either panic, or do nothing.
+ /// A guard for `std::mem::uninitialized`. This will statically either panic, or do nothing.
///
/// This intrinsic does not have a stable counterpart.
#[rustc_const_unstable(feature = "const_assert_type2", issue = "none")]