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(); - /// 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(); + #[cfg(not(bootstrap))] + pub fn assert_mem_uninitialized_valid(); /// 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 { pub unsafe fn uninitialized() -> T { // SAFETY: the caller must guarantee that an uninitialized value is valid for `T`. unsafe { - intrinsics::assert_uninit_valid::(); + #[cfg(not(bootstrap))] // If the compiler hits this itself then it deserves the UB. + intrinsics::assert_mem_uninitialized_valid::(); let mut val = MaybeUninit::::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 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(); - /// 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")]