From 2a899dc1cfe37270cf976b54a2953133faafa0ae Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Thu, 7 Jul 2022 10:46:22 +0000
Subject: [PATCH 01/19] `UnsafeCell` now has no niches, ever.
---
compiler/rustc_attr/src/builtin.rs | 8 +-
.../rustc_const_eval/src/interpret/intern.rs | 2 +-
.../src/interpret/validity.rs | 2 +-
.../src/transform/check_consts/qualifs.rs | 4 +-
compiler/rustc_feature/src/active.rs | 3 -
compiler/rustc_lint/src/types.rs | 2 +-
compiler/rustc_middle/src/ty/adt.rs | 11 +
compiler/rustc_middle/src/ty/layout.rs | 48 +--
compiler/rustc_middle/src/ty/mod.rs | 10 +-
compiler/rustc_passes/src/check_attr.rs | 21 +-
compiler/rustc_span/src/symbol.rs | 2 -
library/core/src/cell.rs | 1 -
library/core/src/lib.rs | 1 -
src/test/ui/layout/unsafe-cell-hides-niche.rs | 5 +-
src/test/ui/lint/clashing-extern-fn.rs | 4 +-
src/test/ui/lint/clashing-extern-fn.stderr | 40 +--
src/test/ui/repr/feature-gate-no-niche.rs | 20 --
src/test/ui/repr/feature-gate-no-niche.stderr | 35 --
.../repr-no-niche-inapplicable-to-unions.rs | 14 -
...epr-no-niche-inapplicable-to-unions.stderr | 19 -
src/test/ui/repr/repr-no-niche.rs | 327 ------------------
.../clippy/clippy_lints/src/non_copy_const.rs | 2 +-
22 files changed, 71 insertions(+), 510 deletions(-)
delete mode 100644 src/test/ui/repr/feature-gate-no-niche.rs
delete mode 100644 src/test/ui/repr/feature-gate-no-niche.stderr
delete mode 100644 src/test/ui/repr/repr-no-niche-inapplicable-to-unions.rs
delete mode 100644 src/test/ui/repr/repr-no-niche-inapplicable-to-unions.stderr
delete mode 100644 src/test/ui/repr/repr-no-niche.rs
diff --git a/compiler/rustc_attr/src/builtin.rs b/compiler/rustc_attr/src/builtin.rs
index ce7c0eb72cd24..6673d75d99df0 100644
--- a/compiler/rustc_attr/src/builtin.rs
+++ b/compiler/rustc_attr/src/builtin.rs
@@ -856,7 +856,6 @@ pub enum ReprAttr {
ReprSimd,
ReprTransparent,
ReprAlign(u32),
- ReprNoNiche,
}
#[derive(Eq, PartialEq, Debug, Copy, Clone)]
@@ -904,7 +903,6 @@ pub fn parse_repr_attr(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
sym::packed => Some(ReprPacked(1)),
sym::simd => Some(ReprSimd),
sym::transparent => Some(ReprTransparent),
- sym::no_niche => Some(ReprNoNiche),
sym::align => {
let mut err = struct_span_err!(
diagnostic,
@@ -943,7 +941,7 @@ pub fn parse_repr_attr(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
Ok(literal) => acc.push(ReprPacked(literal)),
Err(message) => literal_error = Some(message),
};
- } else if matches!(name, sym::C | sym::simd | sym::transparent | sym::no_niche)
+ } else if matches!(name, sym::C | sym::simd | sym::transparent)
|| int_type_of_word(name).is_some()
{
recognised = true;
@@ -1001,7 +999,7 @@ pub fn parse_repr_attr(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
} else {
if matches!(
meta_item.name_or_empty(),
- sym::C | sym::simd | sym::transparent | sym::no_niche
+ sym::C | sym::simd | sym::transparent
) || int_type_of_word(meta_item.name_or_empty()).is_some()
{
recognised = true;
@@ -1039,7 +1037,7 @@ pub fn parse_repr_attr(sess: &Session, attr: &Attribute) -> Vec<ReprAttr> {
.emit();
} else if matches!(
meta_item.name_or_empty(),
- sym::C | sym::simd | sym::transparent | sym::no_niche
+ sym::C | sym::simd | sym::transparent
) || int_type_of_word(meta_item.name_or_empty()).is_some()
{
recognised = true;
diff --git a/compiler/rustc_const_eval/src/interpret/intern.rs b/compiler/rustc_const_eval/src/interpret/intern.rs
index 9dfdafcb38e0b..7616e7a63d107 100644
--- a/compiler/rustc_const_eval/src/interpret/intern.rs
+++ b/compiler/rustc_const_eval/src/interpret/intern.rs
@@ -217,7 +217,7 @@ impl<'rt, 'mir, 'tcx: 'mir, M: CompileTimeMachine<'mir, 'tcx, const_eval::Memory
}
if let Some(def) = mplace.layout.ty.ty_adt_def() {
- if Some(def.did()) == self.ecx.tcx.lang_items().unsafe_cell_type() {
+ if def.is_unsafe_cell() {
// We are crossing over an `UnsafeCell`, we can mutate again. This means that
// References we encounter inside here are interned as pointing to mutable
// allocations.
diff --git a/compiler/rustc_const_eval/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs
index 0bf78446e37fa..48ca5913fabbd 100644
--- a/compiler/rustc_const_eval/src/interpret/validity.rs
+++ b/compiler/rustc_const_eval/src/interpret/validity.rs
@@ -821,7 +821,7 @@ impl<'rt, 'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
// Special check preventing `UnsafeCell` in the inner part of constants
if let Some(def) = op.layout.ty.ty_adt_def() {
if matches!(self.ctfe_mode, Some(CtfeValidationMode::Const { inner: true, .. }))
- && Some(def.did()) == self.ecx.tcx.lang_items().unsafe_cell_type()
+ && def.is_unsafe_cell()
{
throw_validation_failure!(self.path, { "`UnsafeCell` in a `const`" });
}
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
index 6e5a0c813ac20..770286599d25f 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
@@ -96,13 +96,13 @@ impl Qualif for HasMutInterior {
}
fn in_adt_inherently<'tcx>(
- cx: &ConstCx<'_, 'tcx>,
+ _cx: &ConstCx<'_, 'tcx>,
adt: AdtDef<'tcx>,
_: SubstsRef<'tcx>,
) -> bool {
// Exactly one type, `UnsafeCell`, has the `HasMutInterior` qualif inherently.
// It arises structurally for all other types.
- Some(adt.did()) == cx.tcx.lang_items().unsafe_cell_type()
+ adt.is_unsafe_cell()
}
}
diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs
index b54f0ef361a8d..117bdad971a20 100644
--- a/compiler/rustc_feature/src/active.rs
+++ b/compiler/rustc_feature/src/active.rs
@@ -156,9 +156,6 @@ declare_features! (
(active, intrinsics, "1.0.0", None, None),
/// Allows using `#[lang = ".."]` attribute for linking items to special compiler logic.
(active, lang_items, "1.0.0", None, None),
- /// Allows `#[repr(no_niche)]` (an implementation detail of `rustc`,
- /// it is not on path for eventual stabilization).
- (active, no_niche, "1.42.0", None, None),
/// Allows using `#[omit_gdb_pretty_printer_section]`.
(active, omit_gdb_pretty_printer_section, "1.5.0", None, None),
/// Allows using `#[prelude_import]` on glob `use` items.
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index be4843c7ff153..4ed9d9b27b297 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -705,7 +705,7 @@ fn ty_is_known_nonnull<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, mode: CItemKi
// Types with a `#[repr(no_niche)]` attribute have their niche hidden.
// The attribute is used by the UnsafeCell for example (the only use so far).
- if def.repr().hide_niche() {
+ if def.is_unsafe_cell() {
return false;
}
diff --git a/compiler/rustc_middle/src/ty/adt.rs b/compiler/rustc_middle/src/ty/adt.rs
index bf7cb610a9097..9972199c62e04 100644
--- a/compiler/rustc_middle/src/ty/adt.rs
+++ b/compiler/rustc_middle/src/ty/adt.rs
@@ -52,6 +52,8 @@ bitflags! {
/// Indicates whether the variant list of this ADT is `#[non_exhaustive]`.
/// (i.e., this flag is never set unless this ADT is an enum).
const IS_VARIANT_LIST_NON_EXHAUSTIVE = 1 << 8;
+ /// Indicates whether the type is `UnsafeCell`.
+ const IS_UNSAFE_CELL = 1 << 9;
}
}
@@ -242,6 +244,9 @@ impl AdtDefData {
if Some(did) == tcx.lang_items().manually_drop() {
flags |= AdtFlags::IS_MANUALLY_DROP;
}
+ if Some(did) == tcx.lang_items().unsafe_cell_type() {
+ flags |= AdtFlags::IS_UNSAFE_CELL;
+ }
AdtDefData { did, variants, flags, repr }
}
@@ -328,6 +333,12 @@ impl<'tcx> AdtDef<'tcx> {
self.flags().contains(AdtFlags::IS_BOX)
}
+ /// Returns `true` if this is UnsafeCell<T>.
+ #[inline]
+ pub fn is_unsafe_cell(self) -> bool {
+ self.flags().contains(AdtFlags::IS_UNSAFE_CELL)
+ }
+
/// Returns `true` if this is `ManuallyDrop<T>`.
#[inline]
pub fn is_manually_drop(self) -> bool {
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index f87b6e4212d29..cef8a1dba7f8d 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -542,14 +542,12 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
debug!("univariant offset: {:?} field: {:#?}", offset, field);
offsets[i as usize] = offset;
- if !repr.hide_niche() {
- if let Some(mut niche) = field.largest_niche {
- let available = niche.available(dl);
- if available > largest_niche_available {
- largest_niche_available = available;
- niche.offset += offset;
- largest_niche = Some(niche);
- }
+ if let Some(mut niche) = field.largest_niche {
+ let available = niche.available(dl);
+ if available > largest_niche_available {
+ largest_niche_available = available;
+ niche.offset += offset;
+ largest_niche = Some(niche);
}
}
@@ -1104,23 +1102,29 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
assert!(valid_range.end >= end);
valid_range.end = end;
}
-
- // Update `largest_niche` if we have introduced a larger niche.
- let niche = if def.repr().hide_niche() {
- None
+ if def.is_unsafe_cell() {
+ match scalar {
+ Scalar::Initialized { value, valid_range } => {
+ *valid_range = WrappingRange::full(value.size(dl))
+ }
+ // Already doesn't have any niches
+ Scalar::Union { .. } => {}
+ }
+ st.largest_niche = None;
} else {
- Niche::from_scalar(dl, Size::ZERO, *scalar)
- };
- if let Some(niche) = niche {
- match st.largest_niche {
- Some(largest_niche) => {
- // Replace the existing niche even if they're equal,
- // because this one is at a lower offset.
- if largest_niche.available(dl) <= niche.available(dl) {
- st.largest_niche = Some(niche);
+ // Update `largest_niche` if we have introduced a larger niche.
+ let niche = Niche::from_scalar(dl, Size::ZERO, *scalar);
+ if let Some(niche) = niche {
+ match st.largest_niche {
+ Some(largest_niche) => {
+ // Replace the existing niche even if they're equal,
+ // because this one is at a lower offset.
+ if largest_niche.available(dl) <= niche.available(dl) {
+ st.largest_niche = Some(niche);
+ }
}
+ None => st.largest_niche = Some(niche),
}
- None => st.largest_niche = Some(niche),
}
}
}
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index 3a795af2121d0..058cf1a4183df 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -1719,11 +1719,9 @@ bitflags! {
const IS_TRANSPARENT = 1 << 2;
// Internal only for now. If true, don't reorder fields.
const IS_LINEAR = 1 << 3;
- // If true, don't expose any niche to type's context.
- const HIDE_NICHE = 1 << 4;
// If true, the type's layout can be randomized using
// the seed stored in `ReprOptions.layout_seed`
- const RANDOMIZE_LAYOUT = 1 << 5;
+ const RANDOMIZE_LAYOUT = 1 << 4;
// Any of these flags being set prevent field reordering optimisation.
const IS_UNOPTIMISABLE = ReprFlags::IS_C.bits
| ReprFlags::IS_SIMD.bits
@@ -1780,7 +1778,6 @@ impl ReprOptions {
ReprFlags::empty()
}
attr::ReprTransparent => ReprFlags::IS_TRANSPARENT,
- attr::ReprNoNiche => ReprFlags::HIDE_NICHE,
attr::ReprSimd => ReprFlags::IS_SIMD,
attr::ReprInt(i) => {
size = Some(i);
@@ -1833,11 +1830,6 @@ impl ReprOptions {
self.flags.contains(ReprFlags::IS_LINEAR)
}
- #[inline]
- pub fn hide_niche(&self) -> bool {
- self.flags.contains(ReprFlags::HIDE_NICHE)
- }
-
/// Returns the discriminant type, given these `repr` options.
/// This must only be called on enums!
pub fn discr_type(&self) -> attr::IntType {
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index 8c123c052e5ac..cd5357d796d9a 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -1808,21 +1808,6 @@ impl CheckAttrVisitor<'_> {
_ => ("a", "struct, enum, or union"),
}
}
- sym::no_niche => {
- if !self.tcx.features().enabled(sym::no_niche) {
- feature_err(
- &self.tcx.sess.parse_sess,
- sym::no_niche,
- hint.span(),
- "the attribute `repr(no_niche)` is currently unstable",
- )
- .emit();
- }
- match target {
- Target::Struct | Target::Enum => continue,
- _ => ("a", "struct or enum"),
- }
- }
sym::i8
| sym::u8
| sym::i16
@@ -1870,10 +1855,8 @@ impl CheckAttrVisitor<'_> {
// This is not ideal, but tracking precisely which ones are at fault is a huge hassle.
let hint_spans = hints.iter().map(|hint| hint.span());
- // Error on repr(transparent, <anything else apart from no_niche>).
- let non_no_niche = |hint: &&NestedMetaItem| hint.name_or_empty() != sym::no_niche;
- let non_no_niche_count = hints.iter().filter(non_no_niche).count();
- if is_transparent && non_no_niche_count > 1 {
+ // Error on repr(transparent, <anything else>).
+ if is_transparent && hints.len() > 1 {
let hint_spans: Vec<_> = hint_spans.clone().collect();
struct_span_err!(
self.tcx.sess,
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 65a2a18e02f8f..43312105fd6b0 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -979,7 +979,6 @@ symbols! {
no_link,
no_main,
no_mangle,
- no_niche,
no_sanitize,
no_stack_check,
no_start,
@@ -1152,7 +1151,6 @@ symbols! {
repr128,
repr_align,
repr_align_enum,
- repr_no_niche,
repr_packed,
repr_simd,
repr_transparent,
diff --git a/library/core/src/cell.rs b/library/core/src/cell.rs
index 63c83ddb6f7cf..8a37fadc56f4c 100644
--- a/library/core/src/cell.rs
+++ b/library/core/src/cell.rs
@@ -1856,7 +1856,6 @@ impl<T: ?Sized + fmt::Display> fmt::Display for RefMut<'_, T> {
#[lang = "unsafe_cell"]
#[stable(feature = "rust1", since = "1.0.0")]
#[repr(transparent)]
-#[repr(no_niche)] // rust-lang/rust#68303.
pub struct UnsafeCell<T: ?Sized> {
value: T,
}
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 093c7d298734a..19775e7acda2f 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -191,7 +191,6 @@
#![feature(never_type)]
#![feature(no_core)]
#![feature(no_coverage)] // rust-lang/rust#84605
-#![feature(no_niche)] // rust-lang/rust#68303
#![feature(platform_intrinsics)]
#![feature(prelude_import)]
#![feature(repr_simd)]
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 4ca3f7a1aad94..eb65756a5f643 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -5,8 +5,6 @@
// run-pass
-#![feature(no_niche)]
-
use std::cell::UnsafeCell;
use std::mem::size_of;
use std::num::NonZeroU32 as N32;
@@ -16,8 +14,7 @@ struct Wrapper<T>(T);
#[repr(transparent)]
struct Transparent<T>(T);
-#[repr(no_niche)]
-struct NoNiche<T>(T);
+struct NoNiche<T>(UnsafeCell<T>);
fn main() {
assert_eq!(size_of::<Option<Wrapper<u32>>>(), 8);
diff --git a/src/test/ui/lint/clashing-extern-fn.rs b/src/test/ui/lint/clashing-extern-fn.rs
index 2ce4dd56eab0d..809e0602671fe 100644
--- a/src/test/ui/lint/clashing-extern-fn.rs
+++ b/src/test/ui/lint/clashing-extern-fn.rs
@@ -1,7 +1,6 @@
// check-pass
// aux-build:external_extern_fn.rs
#![crate_type = "lib"]
-#![feature(no_niche)]
#![warn(clashing_extern_declarations)]
mod redeclared_different_signature {
@@ -400,9 +399,8 @@ mod hidden_niche {
#[repr(transparent)]
struct Transparent { x: NonZeroUsize }
- #[repr(no_niche)]
#[repr(transparent)]
- struct TransparentNoNiche { y: NonZeroUsize }
+ struct TransparentNoNiche { y: UnsafeCell<NonZeroUsize> }
extern "C" {
fn hidden_niche_transparent() -> Option<Transparent>;
diff --git a/src/test/ui/lint/clashing-extern-fn.stderr b/src/test/ui/lint/clashing-extern-fn.stderr
index a856de322c8ca..4607f68499322 100644
--- a/src/test/ui/lint/clashing-extern-fn.stderr
+++ b/src/test/ui/lint/clashing-extern-fn.stderr
@@ -1,5 +1,5 @@
warning: `clash` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:15:13
+ --> $DIR/clashing-extern-fn.rs:14:13
|
LL | fn clash(x: u8);
| ---------------- `clash` previously declared here
@@ -8,7 +8,7 @@ LL | fn clash(x: u64);
| ^^^^^^^^^^^^^^^^^ this signature doesn't match the previous declaration
|
note: the lint level is defined here
- --> $DIR/clashing-extern-fn.rs:5:9
+ --> $DIR/clashing-extern-fn.rs:4:9
|
LL | #![warn(clashing_extern_declarations)]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -16,7 +16,7 @@ LL | #![warn(clashing_extern_declarations)]
found `unsafe extern "C" fn(u64)`
warning: `extern_link_name` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:53:9
+ --> $DIR/clashing-extern-fn.rs:52:9
|
LL | / #[link_name = "extern_link_name"]
LL | | fn some_new_name(x: i16);
@@ -29,7 +29,7 @@ LL | fn extern_link_name(x: u32);
found `unsafe extern "C" fn(u32)`
warning: `some_other_extern_link_name` redeclares `some_other_new_name` with a different signature
- --> $DIR/clashing-extern-fn.rs:56:9
+ --> $DIR/clashing-extern-fn.rs:55:9
|
LL | fn some_other_new_name(x: i16);
| ------------------------------- `some_other_new_name` previously declared here
@@ -43,7 +43,7 @@ LL | | fn some_other_extern_link_name(x: u32);
found `unsafe extern "C" fn(u32)`
warning: `other_both_names_different` redeclares `link_name_same` with a different signature
- --> $DIR/clashing-extern-fn.rs:60:9
+ --> $DIR/clashing-extern-fn.rs:59:9
|
LL | / #[link_name = "link_name_same"]
LL | | fn both_names_different(x: i16);
@@ -58,7 +58,7 @@ LL | | fn other_both_names_different(x: u32);
found `unsafe extern "C" fn(u32)`
warning: `different_mod` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:73:9
+ --> $DIR/clashing-extern-fn.rs:72:9
|
LL | fn different_mod(x: u8);
| ------------------------ `different_mod` previously declared here
@@ -70,7 +70,7 @@ LL | fn different_mod(x: u64);
found `unsafe extern "C" fn(u64)`
warning: `variadic_decl` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:83:9
+ --> $DIR/clashing-extern-fn.rs:82:9
|
LL | fn variadic_decl(x: u8, ...);
| ----------------------------- `variadic_decl` previously declared here
@@ -82,7 +82,7 @@ LL | fn variadic_decl(x: u8);
found `unsafe extern "C" fn(u8)`
warning: `weigh_banana` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:143:13
+ --> $DIR/clashing-extern-fn.rs:142:13
|
LL | fn weigh_banana(count: *const Banana) -> u64;
| --------------------------------------------- `weigh_banana` previously declared here
@@ -94,7 +94,7 @@ LL | fn weigh_banana(count: *const Banana) -> u64;
found `unsafe extern "C" fn(*const three::Banana) -> u64`
warning: `draw_point` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:172:13
+ --> $DIR/clashing-extern-fn.rs:171:13
|
LL | fn draw_point(p: Point);
| ------------------------ `draw_point` previously declared here
@@ -106,7 +106,7 @@ LL | fn draw_point(p: Point);
found `unsafe extern "C" fn(sameish_members::b::Point)`
warning: `origin` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:198:13
+ --> $DIR/clashing-extern-fn.rs:197:13
|
LL | fn origin() -> Point3;
| ---------------------- `origin` previously declared here
@@ -118,7 +118,7 @@ LL | fn origin() -> Point3;
found `unsafe extern "C" fn() -> same_sized_members_clash::b::Point3`
warning: `transparent_incorrect` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:221:13
+ --> $DIR/clashing-extern-fn.rs:220:13
|
LL | fn transparent_incorrect() -> T;
| -------------------------------- `transparent_incorrect` previously declared here
@@ -130,7 +130,7 @@ LL | fn transparent_incorrect() -> isize;
found `unsafe extern "C" fn() -> isize`
warning: `missing_return_type` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:239:13
+ --> $DIR/clashing-extern-fn.rs:238:13
|
LL | fn missing_return_type() -> usize;
| ---------------------------------- `missing_return_type` previously declared here
@@ -142,7 +142,7 @@ LL | fn missing_return_type();
found `unsafe extern "C" fn()`
warning: `non_zero_usize` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:257:13
+ --> $DIR/clashing-extern-fn.rs:256:13
|
LL | fn non_zero_usize() -> core::num::NonZeroUsize;
| ----------------------------------------------- `non_zero_usize` previously declared here
@@ -154,7 +154,7 @@ LL | fn non_zero_usize() -> usize;
found `unsafe extern "C" fn() -> usize`
warning: `non_null_ptr` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:259:13
+ --> $DIR/clashing-extern-fn.rs:258:13
|
LL | fn non_null_ptr() -> core::ptr::NonNull<usize>;
| ----------------------------------------------- `non_null_ptr` previously declared here
@@ -166,7 +166,7 @@ LL | fn non_null_ptr() -> *const usize;
found `unsafe extern "C" fn() -> *const usize`
warning: `option_non_zero_usize_incorrect` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:357:13
+ --> $DIR/clashing-extern-fn.rs:356:13
|
LL | fn option_non_zero_usize_incorrect() -> usize;
| ---------------------------------------------- `option_non_zero_usize_incorrect` previously declared here
@@ -178,7 +178,7 @@ LL | fn option_non_zero_usize_incorrect() -> isize;
found `unsafe extern "C" fn() -> isize`
warning: `option_non_null_ptr_incorrect` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:359:13
+ --> $DIR/clashing-extern-fn.rs:358:13
|
LL | fn option_non_null_ptr_incorrect() -> *const usize;
| --------------------------------------------------- `option_non_null_ptr_incorrect` previously declared here
@@ -190,7 +190,7 @@ LL | fn option_non_null_ptr_incorrect() -> *const isize;
found `unsafe extern "C" fn() -> *const isize`
warning: `hidden_niche_transparent_no_niche` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:410:13
+ --> $DIR/clashing-extern-fn.rs:408:13
|
LL | fn hidden_niche_transparent_no_niche() -> usize;
| ------------------------------------------------ `hidden_niche_transparent_no_niche` previously declared here
@@ -202,7 +202,7 @@ LL | fn hidden_niche_transparent_no_niche() -> Option<TransparentNoN
found `unsafe extern "C" fn() -> Option<TransparentNoNiche>`
warning: `hidden_niche_unsafe_cell` redeclared with a different signature
- --> $DIR/clashing-extern-fn.rs:414:13
+ --> $DIR/clashing-extern-fn.rs:412:13
|
LL | fn hidden_niche_unsafe_cell() -> usize;
| --------------------------------------- `hidden_niche_unsafe_cell` previously declared here
@@ -214,7 +214,7 @@ LL | fn hidden_niche_unsafe_cell() -> Option<UnsafeCell<NonZeroUsize
found `unsafe extern "C" fn() -> Option<UnsafeCell<NonZeroUsize>>`
warning: `extern` block uses type `Option<TransparentNoNiche>`, which is not FFI-safe
- --> $DIR/clashing-extern-fn.rs:410:55
+ --> $DIR/clashing-extern-fn.rs:408:55
|
LL | fn hidden_niche_transparent_no_niche() -> Option<TransparentNoNiche>;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
@@ -224,7 +224,7 @@ LL | fn hidden_niche_transparent_no_niche() -> Option<TransparentNoN
= note: enum has no representation hint
warning: `extern` block uses type `Option<UnsafeCell<NonZeroUsize>>`, which is not FFI-safe
- --> $DIR/clashing-extern-fn.rs:414:46
+ --> $DIR/clashing-extern-fn.rs:412:46
|
LL | fn hidden_niche_unsafe_cell() -> Option<UnsafeCell<NonZeroUsize>>;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not FFI-safe
diff --git a/src/test/ui/repr/feature-gate-no-niche.rs b/src/test/ui/repr/feature-gate-no-niche.rs
deleted file mode 100644
index 8872ee7119e4a..0000000000000
--- a/src/test/ui/repr/feature-gate-no-niche.rs
+++ /dev/null
@@ -1,20 +0,0 @@
-use std::num::NonZeroU8 as N8;
-use std::num::NonZeroU16 as N16;
-
-#[repr(no_niche)]
-pub struct Cloaked(N16);
-//~^^ ERROR the attribute `repr(no_niche)` is currently unstable [E0658]
-
-#[repr(transparent, no_niche)]
-pub struct Shadowy(N16);
-//~^^ ERROR the attribute `repr(no_niche)` is currently unstable [E0658]
-
-#[repr(no_niche)]
-pub enum Cloaked1 { _A(N16), }
-//~^^ ERROR the attribute `repr(no_niche)` is currently unstable [E0658]
-
-#[repr(no_niche)]
-pub enum Cloaked2 { _A(N16), _B(u8, N8) }
-//~^^ ERROR the attribute `repr(no_niche)` is currently unstable [E0658]
-
-fn main() { }
diff --git a/src/test/ui/repr/feature-gate-no-niche.stderr b/src/test/ui/repr/feature-gate-no-niche.stderr
deleted file mode 100644
index 34fd417cc99a2..0000000000000
--- a/src/test/ui/repr/feature-gate-no-niche.stderr
+++ /dev/null
@@ -1,35 +0,0 @@
-error[E0658]: the attribute `repr(no_niche)` is currently unstable
- --> $DIR/feature-gate-no-niche.rs:4:8
- |
-LL | #[repr(no_niche)]
- | ^^^^^^^^
- |
- = help: add `#![feature(no_niche)]` to the crate attributes to enable
-
-error[E0658]: the attribute `repr(no_niche)` is currently unstable
- --> $DIR/feature-gate-no-niche.rs:8:21
- |
-LL | #[repr(transparent, no_niche)]
- | ^^^^^^^^
- |
- = help: add `#![feature(no_niche)]` to the crate attributes to enable
-
-error[E0658]: the attribute `repr(no_niche)` is currently unstable
- --> $DIR/feature-gate-no-niche.rs:12:8
- |
-LL | #[repr(no_niche)]
- | ^^^^^^^^
- |
- = help: add `#![feature(no_niche)]` to the crate attributes to enable
-
-error[E0658]: the attribute `repr(no_niche)` is currently unstable
- --> $DIR/feature-gate-no-niche.rs:16:8
- |
-LL | #[repr(no_niche)]
- | ^^^^^^^^
- |
- = help: add `#![feature(no_niche)]` to the crate attributes to enable
-
-error: aborting due to 4 previous errors
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/repr/repr-no-niche-inapplicable-to-unions.rs b/src/test/ui/repr/repr-no-niche-inapplicable-to-unions.rs
deleted file mode 100644
index 870eda89c20d7..0000000000000
--- a/src/test/ui/repr/repr-no-niche-inapplicable-to-unions.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-#![feature(no_niche)]
-
-use std::num::NonZeroU8 as N8;
-use std::num::NonZeroU16 as N16;
-
-#[repr(no_niche)]
-pub union Cloaked1 { _A: N16 }
-//~^^ ERROR attribute should be applied to a struct or enum [E0517]
-
-#[repr(no_niche)]
-pub union Cloaked2 { _A: N16, _B: (u8, N8) }
-//~^^ ERROR attribute should be applied to a struct or enum [E0517]
-
-fn main() { }
diff --git a/src/test/ui/repr/repr-no-niche-inapplicable-to-unions.stderr b/src/test/ui/repr/repr-no-niche-inapplicable-to-unions.stderr
deleted file mode 100644
index 9af929d409473..0000000000000
--- a/src/test/ui/repr/repr-no-niche-inapplicable-to-unions.stderr
+++ /dev/null
@@ -1,19 +0,0 @@
-error[E0517]: attribute should be applied to a struct or enum
- --> $DIR/repr-no-niche-inapplicable-to-unions.rs:6:8
- |
-LL | #[repr(no_niche)]
- | ^^^^^^^^
-LL | pub union Cloaked1 { _A: N16 }
- | ------------------------------ not a struct or enum
-
-error[E0517]: attribute should be applied to a struct or enum
- --> $DIR/repr-no-niche-inapplicable-to-unions.rs:10:8
- |
-LL | #[repr(no_niche)]
- | ^^^^^^^^
-LL | pub union Cloaked2 { _A: N16, _B: (u8, N8) }
- | -------------------------------------------- not a struct or enum
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0517`.
diff --git a/src/test/ui/repr/repr-no-niche.rs b/src/test/ui/repr/repr-no-niche.rs
deleted file mode 100644
index 2e6064aeb0074..0000000000000
--- a/src/test/ui/repr/repr-no-niche.rs
+++ /dev/null
@@ -1,327 +0,0 @@
-// run-pass
-
-// This file tests repr(no_niche), which causes an struct/enum to hide
-// any niche space that may exist in its internal state from the
-// context it appears in.
-
-// Here are the axes this test is seeking to cover:
-//
-// repr annotation:
-// visible: (); cloaked: (no_niche); transparent: (transparent); shadowy: (transparent, no_niche)
-//
-// enum vs struct
-//
-// niche-type via type-parameter vs inline declaration
-
-#![feature(decl_macro)]
-#![feature(no_niche)]
-
-use std::mem::size_of;
-use std::num::{NonZeroU8, NonZeroU16};
-
-mod struct_inline {
- use std::num::NonZeroU16 as N16;
-
- #[derive(Debug)] pub struct Visible(N16);
-
- #[repr(no_niche)]
- #[derive(Debug)] pub struct Cloaked(N16);
-
- #[repr(transparent)]
- #[derive(Debug)] pub struct Transparent(N16);
-
- #[repr(transparent, no_niche)]
- #[derive(Debug)] pub struct Shadowy(N16);
-}
-
-mod struct_param {
- #[derive(Debug)] pub struct Visible<T>(T);
-
- #[repr(no_niche)]
- #[derive(Debug)] pub struct Cloaked<T>(T);
-
- #[repr(transparent)]
- #[derive(Debug)] pub struct Transparent<T>(T);
-
- #[repr(transparent, no_niche)]
- #[derive(Debug)] pub struct Shadowy<T>(T);
-}
-
-mod enum_inline {
- use crate::two_fifty_six_variant_enum;
- use std::num::{NonZeroU8 as N8, NonZeroU16 as N16};
-
- #[derive(Debug)] pub enum Visible1 { _A(N16), }
-
- #[repr(no_niche)]
- #[derive(Debug)] pub enum Cloaked1 { _A(N16), }
-
- // (N.B.: transparent enums must be univariant)
- #[repr(transparent)]
- #[derive(Debug)] pub enum Transparent { _A(N16), }
-
- #[repr(transparent, no_niche)]
- #[derive(Debug)] pub enum Shadowy { _A(N16), }
-
- // including multivariant enums for completeness. Payload and
- // number of variants (i.e. discriminant size) have been chosen so
- // that layout including discriminant is 4 bytes, with no space in
- // padding to hide another discrimnant from the surrounding
- // context.
- //
- // (Note that multivariant enums cannot usefully expose a niche in
- // general; this test is relying on that.)
- two_fifty_six_variant_enum!(Visible2, N8);
-
- two_fifty_six_variant_enum!(#[repr(no_niche)] Cloaked2, N8);
-}
-
-mod enum_param {
- use super::two_fifty_six_variant_enum;
-
- #[derive(Debug)] pub enum Visible1<T> { _A(T), }
-
- #[repr(no_niche)]
- #[derive(Debug)] pub enum Cloaked1<T> { _A(T), }
-
- // (N.B.: transparent enums must be univariant)
- #[repr(transparent)]
- #[derive(Debug)] pub enum Transparent<T> { _A(T), }
-
- #[repr(transparent, no_niche)]
- #[derive(Debug)] pub enum Shadowy<T> { _A(T), }
-
- // including multivariant enums for completeness. Same notes apply
- // here as above (assuming `T` is instantiated with `NonZeroU8`).
- two_fifty_six_variant_enum!(Visible2<T>);
-
- two_fifty_six_variant_enum!(#[repr(no_niche)] Cloaked2<T>);
-}
-
-fn main() {
- // sanity-checks
- assert_eq!(size_of::<struct_inline::Visible>(), 2);
- assert_eq!(size_of::<struct_inline::Cloaked>(), 2);
- assert_eq!(size_of::<struct_inline::Transparent>(), 2);
- assert_eq!(size_of::<struct_inline::Shadowy>(), 2);
-
- assert_eq!(size_of::<struct_param::Visible<NonZeroU16>>(), 2);
- assert_eq!(size_of::<struct_param::Cloaked<NonZeroU16>>(), 2);
- assert_eq!(size_of::<struct_param::Transparent<NonZeroU16>>(), 2);
- assert_eq!(size_of::<struct_param::Shadowy<NonZeroU16>>(), 2);
-
- assert_eq!(size_of::<enum_inline::Visible1>(), 2);
- assert_eq!(size_of::<enum_inline::Cloaked1>(), 2);
- assert_eq!(size_of::<enum_inline::Transparent>(), 2); // transparent enums are univariant
- assert_eq!(size_of::<enum_inline::Shadowy>(), 2);
- assert_eq!(size_of::<enum_inline::Visible2>(), 4);
- assert_eq!(size_of::<enum_inline::Cloaked2>(), 4);
-
- assert_eq!(size_of::<enum_param::Visible1<NonZeroU16>>(), 2);
- assert_eq!(size_of::<enum_param::Cloaked1<NonZeroU16>>(), 2);
- assert_eq!(size_of::<enum_param::Transparent<NonZeroU16>>(), 2);
- assert_eq!(size_of::<enum_param::Shadowy<NonZeroU16>>(), 2);
- assert_eq!(size_of::<enum_param::Visible2<NonZeroU8>>(), 4);
- assert_eq!(size_of::<enum_param::Cloaked2<NonZeroU8>>(), 4);
-
- // now the actual tests of no_niche: how do inputs above compose
- // with `Option` type constructor. The cases with a `_+2` are the
- // ones where no_niche fires.
- assert_eq!(size_of::<Option<struct_inline::Visible>>(), 2);
- assert_eq!(size_of::<Option<struct_inline::Cloaked>>(), 2+2);
- assert_eq!(size_of::<Option<struct_inline::Transparent>>(), 2);
- assert_eq!(size_of::<Option<struct_inline::Shadowy>>(), 2+2);
-
- assert_eq!(size_of::<Option<struct_param::Visible<NonZeroU16>>>(), 2);
- assert_eq!(size_of::<Option<struct_param::Cloaked<NonZeroU16>>>(), 2+2);
- assert_eq!(size_of::<Option<struct_param::Transparent<NonZeroU16>>>(), 2);
- assert_eq!(size_of::<Option<struct_param::Shadowy<NonZeroU16>>>(), 2+2);
-
- assert_eq!(size_of::<Option<enum_inline::Visible1>>(), 2);
- assert_eq!(size_of::<Option<enum_inline::Cloaked1>>(), 2+2);
- assert_eq!(size_of::<Option<enum_inline::Transparent>>(), 2);
- assert_eq!(size_of::<Option<enum_inline::Shadowy>>(), 2+2);
- // cannot use niche of multivariant payload
- assert_eq!(size_of::<Option<enum_inline::Visible2>>(), 4+2);
- assert_eq!(size_of::<Option<enum_inline::Cloaked2>>(), 4+2);
-
- assert_eq!(size_of::<Option<enum_param::Visible1<NonZeroU16>>>(), 2);
- assert_eq!(size_of::<Option<enum_param::Cloaked1<NonZeroU16>>>(), 2+2);
- assert_eq!(size_of::<Option<enum_param::Transparent<NonZeroU16>>>(), 2);
- assert_eq!(size_of::<Option<enum_param::Shadowy<NonZeroU16>>>(), 2+2);
- // cannot use niche of multivariant payload
- assert_eq!(size_of::<Option<enum_param::Visible2<NonZeroU8>>>(), 4+2);
- assert_eq!(size_of::<Option<enum_param::Cloaked2<NonZeroU8>>>(), 4+2);
-}
-
-macro two_fifty_six_variant_enum {
- ($(#[$attr:meta])* $name:ident<$param:ident>) => {
- #[derive(Debug)] $(#[$attr])*
- pub enum $name<$param> {
- _V00($param, u16), _V01(u16, $param), _V02($param, u16), _V03(u16, $param),
- _V04($param, u16), _V05(u16, $param), _V06($param, u16), _V07(u16, $param),
- _V08($param, u16), _V09(u16, $param), _V0a($param, u16), _V0b(u16, $param),
- _V0c($param, u16), _V0d(u16, $param), _V0e($param, u16), _V0f(u16, $param),
-
- _V10($param, u16), _V11(u16, $param), _V12($param, u16), _V13(u16, $param),
- _V14($param, u16), _V15(u16, $param), _V16($param, u16), _V17(u16, $param),
- _V18($param, u16), _V19(u16, $param), _V1a($param, u16), _V1b(u16, $param),
- _V1c($param, u16), _V1d(u16, $param), _V1e($param, u16), _V1f(u16, $param),
-
- _V20($param, u16), _V21(u16, $param), _V22($param, u16), _V23(u16, $param),
- _V24($param, u16), _V25(u16, $param), _V26($param, u16), _V27(u16, $param),
- _V28($param, u16), _V29(u16, $param), _V2a($param, u16), _V2b(u16, $param),
- _V2c($param, u16), _V2d(u16, $param), _V2e($param, u16), _V2f(u16, $param),
-
- _V30($param, u16), _V31(u16, $param), _V32($param, u16), _V33(u16, $param),
- _V34($param, u16), _V35(u16, $param), _V36($param, u16), _V37(u16, $param),
- _V38($param, u16), _V39(u16, $param), _V3a($param, u16), _V3b(u16, $param),
- _V3c($param, u16), _V3d(u16, $param), _V3e($param, u16), _V3f(u16, $param),
-
- _V40($param, u16), _V41(u16, $param), _V42($param, u16), _V43(u16, $param),
- _V44($param, u16), _V45(u16, $param), _V46($param, u16), _V47(u16, $param),
- _V48($param, u16), _V49(u16, $param), _V4a($param, u16), _V4b(u16, $param),
- _V4c($param, u16), _V4d(u16, $param), _V4e($param, u16), _V4f(u16, $param),
-
- _V50($param, u16), _V51(u16, $param), _V52($param, u16), _V53(u16, $param),
- _V54($param, u16), _V55(u16, $param), _V56($param, u16), _V57(u16, $param),
- _V58($param, u16), _V59(u16, $param), _V5a($param, u16), _V5b(u16, $param),
- _V5c($param, u16), _V5d(u16, $param), _V5e($param, u16), _V5f(u16, $param),
-
- _V60($param, u16), _V61(u16, $param), _V62($param, u16), _V63(u16, $param),
- _V64($param, u16), _V65(u16, $param), _V66($param, u16), _V67(u16, $param),
- _V68($param, u16), _V69(u16, $param), _V6a($param, u16), _V6b(u16, $param),
- _V6c($param, u16), _V6d(u16, $param), _V6e($param, u16), _V6f(u16, $param),
-
- _V70($param, u16), _V71(u16, $param), _V72($param, u16), _V73(u16, $param),
- _V74($param, u16), _V75(u16, $param), _V76($param, u16), _V77(u16, $param),
- _V78($param, u16), _V79(u16, $param), _V7a($param, u16), _V7b(u16, $param),
- _V7c($param, u16), _V7d(u16, $param), _V7e($param, u16), _V7f(u16, $param),
-
- _V80($param, u16), _V81(u16, $param), _V82($param, u16), _V83(u16, $param),
- _V84($param, u16), _V85(u16, $param), _V86($param, u16), _V87(u16, $param),
- _V88($param, u16), _V89(u16, $param), _V8a($param, u16), _V8b(u16, $param),
- _V8c($param, u16), _V8d(u16, $param), _V8e($param, u16), _V8f(u16, $param),
-
- _V90($param, u16), _V91(u16, $param), _V92($param, u16), _V93(u16, $param),
- _V94($param, u16), _V95(u16, $param), _V96($param, u16), _V97(u16, $param),
- _V98($param, u16), _V99(u16, $param), _V9a($param, u16), _V9b(u16, $param),
- _V9c($param, u16), _V9d(u16, $param), _V9e($param, u16), _V9f(u16, $param),
-
- _Va0($param, u16), _Va1(u16, $param), _Va2($param, u16), _Va3(u16, $param),
- _Va4($param, u16), _Va5(u16, $param), _Va6($param, u16), _Va7(u16, $param),
- _Va8($param, u16), _Va9(u16, $param), _Vaa($param, u16), _Vab(u16, $param),
- _Vac($param, u16), _Vad(u16, $param), _Vae($param, u16), _Vaf(u16, $param),
-
- _Vb0($param, u16), _Vb1(u16, $param), _Vb2($param, u16), _Vb3(u16, $param),
- _Vb4($param, u16), _Vb5(u16, $param), _Vb6($param, u16), _Vb7(u16, $param),
- _Vb8($param, u16), _Vb9(u16, $param), _Vba($param, u16), _Vbb(u16, $param),
- _Vbc($param, u16), _Vbd(u16, $param), _Vbe($param, u16), _Vbf(u16, $param),
-
- _Vc0($param, u16), _Vc1(u16, $param), _Vc2($param, u16), _Vc3(u16, $param),
- _Vc4($param, u16), _Vc5(u16, $param), _Vc6($param, u16), _Vc7(u16, $param),
- _Vc8($param, u16), _Vc9(u16, $param), _Vca($param, u16), _Vcb(u16, $param),
- _Vcc($param, u16), _Vcd(u16, $param), _Vce($param, u16), _Vcf(u16, $param),
-
- _Vd0($param, u16), _Vd1(u16, $param), _Vd2($param, u16), _Vd3(u16, $param),
- _Vd4($param, u16), _Vd5(u16, $param), _Vd6($param, u16), _Vd7(u16, $param),
- _Vd8($param, u16), _Vd9(u16, $param), _Vda($param, u16), _Vdb(u16, $param),
- _Vdc($param, u16), _Vdd(u16, $param), _Vde($param, u16), _Vdf(u16, $param),
-
- _Ve0($param, u16), _Ve1(u16, $param), _Ve2($param, u16), _Ve3(u16, $param),
- _Ve4($param, u16), _Ve5(u16, $param), _Ve6($param, u16), _Ve7(u16, $param),
- _Ve8($param, u16), _Ve9(u16, $param), _Vea($param, u16), _Veb(u16, $param),
- _Vec($param, u16), _Ved(u16, $param), _Vee($param, u16), _Vef(u16, $param),
-
- _Vf0($param, u16), _Vf1(u16, $param), _Vf2($param, u16), _Vf3(u16, $param),
- _Vf4($param, u16), _Vf5(u16, $param), _Vf6($param, u16), _Vf7(u16, $param),
- _Vf8($param, u16), _Vf9(u16, $param), _Vfa($param, u16), _Vfb(u16, $param),
- _Vfc($param, u16), _Vfd(u16, $param), _Vfe($param, u16), _Vff(u16, $param),
- }
- },
-
- ($(#[$attr:meta])* $name:ident, $param:ty) => {
- #[derive(Debug)] $(#[$attr])*
- pub enum $name {
- _V00($param, u16), _V01(u16, $param), _V02($param, u16), _V03(u16, $param),
- _V04($param, u16), _V05(u16, $param), _V06($param, u16), _V07(u16, $param),
- _V08($param, u16), _V09(u16, $param), _V0a($param, u16), _V0b(u16, $param),
- _V0c($param, u16), _V0d(u16, $param), _V0e($param, u16), _V0f(u16, $param),
-
- _V10($param, u16), _V11(u16, $param), _V12($param, u16), _V13(u16, $param),
- _V14($param, u16), _V15(u16, $param), _V16($param, u16), _V17(u16, $param),
- _V18($param, u16), _V19(u16, $param), _V1a($param, u16), _V1b(u16, $param),
- _V1c($param, u16), _V1d(u16, $param), _V1e($param, u16), _V1f(u16, $param),
-
- _V20($param, u16), _V21(u16, $param), _V22($param, u16), _V23(u16, $param),
- _V24($param, u16), _V25(u16, $param), _V26($param, u16), _V27(u16, $param),
- _V28($param, u16), _V29(u16, $param), _V2a($param, u16), _V2b(u16, $param),
- _V2c($param, u16), _V2d(u16, $param), _V2e($param, u16), _V2f(u16, $param),
-
- _V30($param, u16), _V31(u16, $param), _V32($param, u16), _V33(u16, $param),
- _V34($param, u16), _V35(u16, $param), _V36($param, u16), _V37(u16, $param),
- _V38($param, u16), _V39(u16, $param), _V3a($param, u16), _V3b(u16, $param),
- _V3c($param, u16), _V3d(u16, $param), _V3e($param, u16), _V3f(u16, $param),
-
- _V40($param, u16), _V41(u16, $param), _V42($param, u16), _V43(u16, $param),
- _V44($param, u16), _V45(u16, $param), _V46($param, u16), _V47(u16, $param),
- _V48($param, u16), _V49(u16, $param), _V4a($param, u16), _V4b(u16, $param),
- _V4c($param, u16), _V4d(u16, $param), _V4e($param, u16), _V4f(u16, $param),
-
- _V50($param, u16), _V51(u16, $param), _V52($param, u16), _V53(u16, $param),
- _V54($param, u16), _V55(u16, $param), _V56($param, u16), _V57(u16, $param),
- _V58($param, u16), _V59(u16, $param), _V5a($param, u16), _V5b(u16, $param),
- _V5c($param, u16), _V5d(u16, $param), _V5e($param, u16), _V5f(u16, $param),
-
- _V60($param, u16), _V61(u16, $param), _V62($param, u16), _V63(u16, $param),
- _V64($param, u16), _V65(u16, $param), _V66($param, u16), _V67(u16, $param),
- _V68($param, u16), _V69(u16, $param), _V6a($param, u16), _V6b(u16, $param),
- _V6c($param, u16), _V6d(u16, $param), _V6e($param, u16), _V6f(u16, $param),
-
- _V70($param, u16), _V71(u16, $param), _V72($param, u16), _V73(u16, $param),
- _V74($param, u16), _V75(u16, $param), _V76($param, u16), _V77(u16, $param),
- _V78($param, u16), _V79(u16, $param), _V7a($param, u16), _V7b(u16, $param),
- _V7c($param, u16), _V7d(u16, $param), _V7e($param, u16), _V7f(u16, $param),
-
- _V80($param, u16), _V81(u16, $param), _V82($param, u16), _V83(u16, $param),
- _V84($param, u16), _V85(u16, $param), _V86($param, u16), _V87(u16, $param),
- _V88($param, u16), _V89(u16, $param), _V8a($param, u16), _V8b(u16, $param),
- _V8c($param, u16), _V8d(u16, $param), _V8e($param, u16), _V8f(u16, $param),
-
- _V90($param, u16), _V91(u16, $param), _V92($param, u16), _V93(u16, $param),
- _V94($param, u16), _V95(u16, $param), _V96($param, u16), _V97(u16, $param),
- _V98($param, u16), _V99(u16, $param), _V9a($param, u16), _V9b(u16, $param),
- _V9c($param, u16), _V9d(u16, $param), _V9e($param, u16), _V9f(u16, $param),
-
- _Va0($param, u16), _Va1(u16, $param), _Va2($param, u16), _Va3(u16, $param),
- _Va4($param, u16), _Va5(u16, $param), _Va6($param, u16), _Va7(u16, $param),
- _Va8($param, u16), _Va9(u16, $param), _Vaa($param, u16), _Vab(u16, $param),
- _Vac($param, u16), _Vad(u16, $param), _Vae($param, u16), _Vaf(u16, $param),
-
- _Vb0($param, u16), _Vb1(u16, $param), _Vb2($param, u16), _Vb3(u16, $param),
- _Vb4($param, u16), _Vb5(u16, $param), _Vb6($param, u16), _Vb7(u16, $param),
- _Vb8($param, u16), _Vb9(u16, $param), _Vba($param, u16), _Vbb(u16, $param),
- _Vbc($param, u16), _Vbd(u16, $param), _Vbe($param, u16), _Vbf(u16, $param),
-
- _Vc0($param, u16), _Vc1(u16, $param), _Vc2($param, u16), _Vc3(u16, $param),
- _Vc4($param, u16), _Vc5(u16, $param), _Vc6($param, u16), _Vc7(u16, $param),
- _Vc8($param, u16), _Vc9(u16, $param), _Vca($param, u16), _Vcb(u16, $param),
- _Vcc($param, u16), _Vcd(u16, $param), _Vce($param, u16), _Vcf(u16, $param),
-
- _Vd0($param, u16), _Vd1(u16, $param), _Vd2($param, u16), _Vd3(u16, $param),
- _Vd4($param, u16), _Vd5(u16, $param), _Vd6($param, u16), _Vd7(u16, $param),
- _Vd8($param, u16), _Vd9(u16, $param), _Vda($param, u16), _Vdb(u16, $param),
- _Vdc($param, u16), _Vdd(u16, $param), _Vde($param, u16), _Vdf(u16, $param),
-
- _Ve0($param, u16), _Ve1(u16, $param), _Ve2($param, u16), _Ve3(u16, $param),
- _Ve4($param, u16), _Ve5(u16, $param), _Ve6($param, u16), _Ve7(u16, $param),
- _Ve8($param, u16), _Ve9(u16, $param), _Vea($param, u16), _Veb(u16, $param),
- _Vec($param, u16), _Ved(u16, $param), _Vee($param, u16), _Vef(u16, $param),
-
- _Vf0($param, u16), _Vf1(u16, $param), _Vf2($param, u16), _Vf3(u16, $param),
- _Vf4($param, u16), _Vf5(u16, $param), _Vf6($param, u16), _Vf7(u16, $param),
- _Vf8($param, u16), _Vf9(u16, $param), _Vfa($param, u16), _Vfb(u16, $param),
- _Vfc($param, u16), _Vfd(u16, $param), _Vfe($param, u16), _Vff(u16, $param),
- }
- }
-}
diff --git a/src/tools/clippy/clippy_lints/src/non_copy_const.rs b/src/tools/clippy/clippy_lints/src/non_copy_const.rs
index a1ef32ae60805..6bce5fbd4c1fe 100644
--- a/src/tools/clippy/clippy_lints/src/non_copy_const.rs
+++ b/src/tools/clippy/clippy_lints/src/non_copy_const.rs
@@ -148,7 +148,7 @@ fn is_value_unfrozen_raw<'tcx>(
match val.ty().kind() {
// the fact that we have to dig into every structs to search enums
// leads us to the point checking `UnsafeCell` directly is the only option.
- ty::Adt(ty_def, ..) if Some(ty_def.did()) == cx.tcx.lang_items().unsafe_cell_type() => true,
+ ty::Adt(ty_def, ..) if ty_def.is_unsafe_cell() => true,
ty::Array(..) | ty::Adt(..) | ty::Tuple(..) => {
let val = cx.tcx.destructure_mir_constant(cx.param_env, val);
val.fields.iter().any(|field| inner(cx, *field))
From 8d9f609d0d4465285ac9f0257c706c559644fef5 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Thu, 7 Jul 2022 11:19:57 +0000
Subject: [PATCH 02/19] Comment update
---
compiler/rustc_lint/src/types.rs | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index 4ed9d9b27b297..aca481df2e113 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -703,8 +703,7 @@ fn ty_is_known_nonnull<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>, mode: CItemKi
return true;
}
- // Types with a `#[repr(no_niche)]` attribute have their niche hidden.
- // The attribute is used by the UnsafeCell for example (the only use so far).
+ // `UnsafeCell` has its niche hidden.
if def.is_unsafe_cell() {
return false;
}
From 4bfba76a3da28d780be3cb31fd6269b8bc6183df Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Fri, 8 Jul 2022 14:28:19 +0000
Subject: [PATCH 03/19] Add tests for libstd types
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 22 ++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index eb65756a5f643..f6a8e0de27ad0 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -5,9 +5,10 @@
// run-pass
-use std::cell::UnsafeCell;
+use std::cell::{UnsafeCell, RefCell, Cell};
use std::mem::size_of;
use std::num::NonZeroU32 as N32;
+use std::sync::{Mutex, RwLock};
struct Wrapper<T>(T);
@@ -18,12 +19,23 @@ struct NoNiche<T>(UnsafeCell<T>);
fn main() {
assert_eq!(size_of::<Option<Wrapper<u32>>>(), 8);
- assert_eq!(size_of::<Option<Wrapper<N32>>>(), 4);
+ assert_eq!(size_of::<Option<Wrapper<N32>>>(), 4); // (✓ niche opt)
assert_eq!(size_of::<Option<Transparent<u32>>>(), 8);
- assert_eq!(size_of::<Option<Transparent<N32>>>(), 4);
+ assert_eq!(size_of::<Option<Transparent<N32>>>(), 4); // (✓ niche opt)
assert_eq!(size_of::<Option<NoNiche<u32>>>(), 8);
- assert_eq!(size_of::<Option<NoNiche<N32>>>(), 8);
+ assert_eq!(size_of::<Option<NoNiche<N32>>>(), 8); // (✗ niche opt)
assert_eq!(size_of::<Option<UnsafeCell<u32>>>(), 8);
- assert_eq!(size_of::<Option<UnsafeCell<N32>>>(), 8);
+ assert_eq!(size_of::<Option<UnsafeCell<N32>>>(), 8); // (✗ niche opt)
+
+ assert_eq!(size_of::< UnsafeCell<&()> >(), 8);
+ assert_eq!(size_of::<Option<UnsafeCell<&()>>>(), 16); // (✗ niche opt)
+ assert_eq!(size_of::< Cell<&()> >(), 8);
+ assert_eq!(size_of::<Option< Cell<&()>>>(), 16); // (✗ niche opt)
+ assert_eq!(size_of::< RefCell<&()> >(), 16);
+ assert_eq!(size_of::<Option< RefCell<&()>>>(), 24); // (✗ niche opt)
+ assert_eq!(size_of::< RwLock<&()> >(), 24);
+ assert_eq!(size_of::<Option< RwLock<&()>>>(), 32); // (✗ niche opt)
+ assert_eq!(size_of::< Mutex<&()> >(), 16);
+ assert_eq!(size_of::<Option< Mutex<&()>>>(), 24); // (✗ niche opt)
}
From 69b1b3c011143b573c904f0759d187588cc457c0 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Fri, 8 Jul 2022 14:47:25 +0000
Subject: [PATCH 04/19] Create a custom layout path for UnsafeCell instead of
piggy backing on the layout_scalar_valid_range logic
---
compiler/rustc_middle/src/ty/layout.rs | 60 ++++++++++++-------
src/test/ui/layout/unsafe-cell-hides-niche.rs | 9 +++
2 files changed, 48 insertions(+), 21 deletions(-)
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index cef8a1dba7f8d..6d87328ef5daa 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -1076,6 +1076,34 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
let mut st = self.univariant_uninterned(ty, &variants[v], &def.repr(), kind)?;
st.variants = Variants::Single { index: v };
+
+ if def.is_unsafe_cell() {
+ let fill = |scalar: &mut _| match scalar {
+ Scalar::Initialized { value, valid_range } => {
+ *valid_range = WrappingRange::full(value.size(dl))
+ }
+ // Already doesn't have any niches
+ Scalar::Union { .. } => {}
+ };
+ match &mut st.abi {
+ Abi::Uninhabited => {}
+ Abi::Scalar(scalar) => fill(scalar),
+ Abi::ScalarPair(a, b) => {
+ fill(a);
+ fill(b);
+ }
+ Abi::Vector { element, count: _ } => {
+ // Until we support types other than floats and integers in SIMD,
+ // `element` must already be a full for its range, so there's nothing to
+ // do here.
+ assert!(element.is_always_valid(dl));
+ }
+ Abi::Aggregate { sized: _ } => {}
+ }
+ st.largest_niche = None;
+ return Ok(tcx.intern_layout(st));
+ }
+
let (start, end) = self.tcx.layout_scalar_valid_range(def.did());
match st.abi {
Abi::Scalar(ref mut scalar) | Abi::ScalarPair(ref mut scalar, _) => {
@@ -1102,29 +1130,19 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
assert!(valid_range.end >= end);
valid_range.end = end;
}
- if def.is_unsafe_cell() {
- match scalar {
- Scalar::Initialized { value, valid_range } => {
- *valid_range = WrappingRange::full(value.size(dl))
- }
- // Already doesn't have any niches
- Scalar::Union { .. } => {}
- }
- st.largest_niche = None;
- } else {
- // Update `largest_niche` if we have introduced a larger niche.
- let niche = Niche::from_scalar(dl, Size::ZERO, *scalar);
- if let Some(niche) = niche {
- match st.largest_niche {
- Some(largest_niche) => {
- // Replace the existing niche even if they're equal,
- // because this one is at a lower offset.
- if largest_niche.available(dl) <= niche.available(dl) {
- st.largest_niche = Some(niche);
- }
+
+ // Update `largest_niche` if we have introduced a larger niche.
+ let niche = Niche::from_scalar(dl, Size::ZERO, *scalar);
+ if let Some(niche) = niche {
+ match st.largest_niche {
+ Some(largest_niche) => {
+ // Replace the existing niche even if they're equal,
+ // because this one is at a lower offset.
+ if largest_niche.available(dl) <= niche.available(dl) {
+ st.largest_niche = Some(niche);
}
- None => st.largest_niche = Some(niche),
}
+ None => st.largest_niche = Some(niche),
}
}
}
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index f6a8e0de27ad0..2d3bb1d23c093 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -38,4 +38,13 @@ fn main() {
assert_eq!(size_of::<Option< RwLock<&()>>>(), 32); // (✗ niche opt)
assert_eq!(size_of::< Mutex<&()> >(), 16);
assert_eq!(size_of::<Option< Mutex<&()>>>(), 24); // (✗ niche opt)
+
+ assert_eq!(size_of::< UnsafeCell<&[i32]> >(), 16);
+ assert_eq!(size_of::<Option<UnsafeCell<&[i32]>>>(), 24); // (✗ niche opt)
+ assert_eq!(size_of::< UnsafeCell<(&(), &())> >(), 16);
+ assert_eq!(size_of::<Option<UnsafeCell<(&(), &())>>>(), 24); // (✗ niche opt)
+
+ trait Trait {}
+ assert_eq!(size_of::< UnsafeCell<&dyn Trait> >(), 16);
+ assert_eq!(size_of::<Option<UnsafeCell<&dyn Trait>>>(), 24); // (✗ niche opt)
}
From 423915590b08896ecc845b8b22910cb98c4c7e36 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:11:28 +0000
Subject: [PATCH 05/19] More obvious closure name
---
compiler/rustc_middle/src/ty/layout.rs | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index 6d87328ef5daa..8cbc0169bc7a4 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -1078,7 +1078,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
st.variants = Variants::Single { index: v };
if def.is_unsafe_cell() {
- let fill = |scalar: &mut _| match scalar {
+ let hide_niches = |scalar: &mut _| match scalar {
Scalar::Initialized { value, valid_range } => {
*valid_range = WrappingRange::full(value.size(dl))
}
@@ -1087,10 +1087,10 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
};
match &mut st.abi {
Abi::Uninhabited => {}
- Abi::Scalar(scalar) => fill(scalar),
+ Abi::Scalar(scalar) => hide_niches(scalar),
Abi::ScalarPair(a, b) => {
- fill(a);
- fill(b);
+ hide_niches(a);
+ hide_niches(b);
}
Abi::Vector { element, count: _ } => {
// Until we support types other than floats and integers in SIMD,
From 984db78d771ec67d781e954da759dbea8667197a Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:25:41 +0000
Subject: [PATCH 06/19] Hide niches in SIMD types, too
---
compiler/rustc_middle/src/ty/layout.rs | 7 +------
src/test/ui/layout/unsafe-cell-hides-niche.rs | 8 ++++++++
2 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs
index 8cbc0169bc7a4..1ed41db099ca0 100644
--- a/compiler/rustc_middle/src/ty/layout.rs
+++ b/compiler/rustc_middle/src/ty/layout.rs
@@ -1092,12 +1092,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
hide_niches(a);
hide_niches(b);
}
- Abi::Vector { element, count: _ } => {
- // Until we support types other than floats and integers in SIMD,
- // `element` must already be a full for its range, so there's nothing to
- // do here.
- assert!(element.is_always_valid(dl));
- }
+ Abi::Vector { element, count: _ } => hide_niches(element),
Abi::Aggregate { sized: _ } => {}
}
st.largest_niche = None;
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 2d3bb1d23c093..bb2156a5da727 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -5,6 +5,8 @@
// run-pass
+#![feature(repr_simd)]
+
use std::cell::{UnsafeCell, RefCell, Cell};
use std::mem::size_of;
use std::num::NonZeroU32 as N32;
@@ -47,4 +49,10 @@ fn main() {
trait Trait {}
assert_eq!(size_of::< UnsafeCell<&dyn Trait> >(), 16);
assert_eq!(size_of::<Option<UnsafeCell<&dyn Trait>>>(), 24); // (✗ niche opt)
+
+ #[repr(simd)]
+ pub struct Vec4<T>([T; 4]);
+
+ assert_eq!(size_of::< UnsafeCell<Vec4<N32>> >(), 16);
+ assert_eq!(size_of::<Option<UnsafeCell<Vec4<N32>>>>(), 32); // (✗ niche opt)
}
From 3f4cf59323304a2e785aba564a6eb3bd473d5499 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:29:02 +0000
Subject: [PATCH 07/19] Move checks to compile-time
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index bb2156a5da727..385472ac88a7d 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -3,7 +3,7 @@
// test checks that an `Option<UnsafeCell<NonZeroU32>>` has the same
// size in memory as an `Option<UnsafeCell<u32>>` (namely, 8 bytes).
-// run-pass
+// check-pass
#![feature(repr_simd)]
@@ -19,6 +19,13 @@ struct Transparent<T>(T);
struct NoNiche<T>(UnsafeCell<T>);
+// Overwriting the runtime assertion and making it a compile-time assertion
+macro_rules! assert_eq {
+ ($a:expr, $b:literal) => {{
+ const _: () = assert!($a == $b);
+ }};
+}
+
fn main() {
assert_eq!(size_of::<Option<Wrapper<u32>>>(), 8);
assert_eq!(size_of::<Option<Wrapper<N32>>>(), 4); // (✓ niche opt)
From af8536e32ff8840bb41c65a438ccf33568548e02 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:30:50 +0000
Subject: [PATCH 08/19] Simplify assertion macro
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 57 +++++++++----------
1 file changed, 28 insertions(+), 29 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 385472ac88a7d..f5c1fe1320c56 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -8,7 +8,6 @@
#![feature(repr_simd)]
use std::cell::{UnsafeCell, RefCell, Cell};
-use std::mem::size_of;
use std::num::NonZeroU32 as N32;
use std::sync::{Mutex, RwLock};
@@ -21,45 +20,45 @@ struct NoNiche<T>(UnsafeCell<T>);
// Overwriting the runtime assertion and making it a compile-time assertion
macro_rules! assert_eq {
- ($a:expr, $b:literal) => {{
- const _: () = assert!($a == $b);
+ ($a:ty, $b:literal) => {{
+ const _: () = assert!(std::mem::size_of::<$a>() == $b);
}};
}
fn main() {
- assert_eq!(size_of::<Option<Wrapper<u32>>>(), 8);
- assert_eq!(size_of::<Option<Wrapper<N32>>>(), 4); // (✓ niche opt)
- assert_eq!(size_of::<Option<Transparent<u32>>>(), 8);
- assert_eq!(size_of::<Option<Transparent<N32>>>(), 4); // (✓ niche opt)
- assert_eq!(size_of::<Option<NoNiche<u32>>>(), 8);
- assert_eq!(size_of::<Option<NoNiche<N32>>>(), 8); // (✗ niche opt)
+ assert_eq!(Option<Wrapper<u32>>, 8);
+ assert_eq!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
+ assert_eq!(Option<Transparent<u32>>, 8);
+ assert_eq!(Option<Transparent<N32>>, 4); // (✓ niche opt)
+ assert_eq!(Option<NoNiche<u32>>, 8);
+ assert_eq!(Option<NoNiche<N32>>, 8); // (✗ niche opt)
- assert_eq!(size_of::<Option<UnsafeCell<u32>>>(), 8);
- assert_eq!(size_of::<Option<UnsafeCell<N32>>>(), 8); // (✗ niche opt)
+ assert_eq!(Option<UnsafeCell<u32>>, 8);
+ assert_eq!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
- assert_eq!(size_of::< UnsafeCell<&()> >(), 8);
- assert_eq!(size_of::<Option<UnsafeCell<&()>>>(), 16); // (✗ niche opt)
- assert_eq!(size_of::< Cell<&()> >(), 8);
- assert_eq!(size_of::<Option< Cell<&()>>>(), 16); // (✗ niche opt)
- assert_eq!(size_of::< RefCell<&()> >(), 16);
- assert_eq!(size_of::<Option< RefCell<&()>>>(), 24); // (✗ niche opt)
- assert_eq!(size_of::< RwLock<&()> >(), 24);
- assert_eq!(size_of::<Option< RwLock<&()>>>(), 32); // (✗ niche opt)
- assert_eq!(size_of::< Mutex<&()> >(), 16);
- assert_eq!(size_of::<Option< Mutex<&()>>>(), 24); // (✗ niche opt)
+ assert_eq!( UnsafeCell<&()> , 8);
+ assert_eq!(Option<UnsafeCell<&()>>, 16); // (✗ niche opt)
+ assert_eq!( Cell<&()> , 8);
+ assert_eq!(Option< Cell<&()>>, 16); // (✗ niche opt)
+ assert_eq!( RefCell<&()> , 16);
+ assert_eq!(Option< RefCell<&()>>, 24); // (✗ niche opt)
+ assert_eq!( RwLock<&()> , 24);
+ assert_eq!(Option< RwLock<&()>>, 32); // (✗ niche opt)
+ assert_eq!( Mutex<&()> , 16);
+ assert_eq!(Option< Mutex<&()>>, 24); // (✗ niche opt)
- assert_eq!(size_of::< UnsafeCell<&[i32]> >(), 16);
- assert_eq!(size_of::<Option<UnsafeCell<&[i32]>>>(), 24); // (✗ niche opt)
- assert_eq!(size_of::< UnsafeCell<(&(), &())> >(), 16);
- assert_eq!(size_of::<Option<UnsafeCell<(&(), &())>>>(), 24); // (✗ niche opt)
+ assert_eq!( UnsafeCell<&[i32]> , 16);
+ assert_eq!(Option<UnsafeCell<&[i32]>>, 24); // (✗ niche opt)
+ assert_eq!( UnsafeCell<(&(), &())> , 16);
+ assert_eq!(Option<UnsafeCell<(&(), &())>>, 24); // (✗ niche opt)
trait Trait {}
- assert_eq!(size_of::< UnsafeCell<&dyn Trait> >(), 16);
- assert_eq!(size_of::<Option<UnsafeCell<&dyn Trait>>>(), 24); // (✗ niche opt)
+ assert_eq!( UnsafeCell<&dyn Trait> , 16);
+ assert_eq!(Option<UnsafeCell<&dyn Trait>>, 24); // (✗ niche opt)
#[repr(simd)]
pub struct Vec4<T>([T; 4]);
- assert_eq!(size_of::< UnsafeCell<Vec4<N32>> >(), 16);
- assert_eq!(size_of::<Option<UnsafeCell<Vec4<N32>>>>(), 32); // (✗ niche opt)
+ assert_eq!( UnsafeCell<Vec4<N32>> , 16);
+ assert_eq!(Option<UnsafeCell<Vec4<N32>>>, 32); // (✗ niche opt)
}
From fef596f6a243d311dc50b50f83f8339e326f1f66 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:31:21 +0000
Subject: [PATCH 09/19] Rename assertion macro
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 54 +++++++++----------
1 file changed, 27 insertions(+), 27 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index f5c1fe1320c56..7fb55d8219ef8 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -19,46 +19,46 @@ struct Transparent<T>(T);
struct NoNiche<T>(UnsafeCell<T>);
// Overwriting the runtime assertion and making it a compile-time assertion
-macro_rules! assert_eq {
+macro_rules! assert_size {
($a:ty, $b:literal) => {{
const _: () = assert!(std::mem::size_of::<$a>() == $b);
}};
}
fn main() {
- assert_eq!(Option<Wrapper<u32>>, 8);
- assert_eq!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
- assert_eq!(Option<Transparent<u32>>, 8);
- assert_eq!(Option<Transparent<N32>>, 4); // (✓ niche opt)
- assert_eq!(Option<NoNiche<u32>>, 8);
- assert_eq!(Option<NoNiche<N32>>, 8); // (✗ niche opt)
+ assert_size!(Option<Wrapper<u32>>, 8);
+ assert_size!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
+ assert_size!(Option<Transparent<u32>>, 8);
+ assert_size!(Option<Transparent<N32>>, 4); // (✓ niche opt)
+ assert_size!(Option<NoNiche<u32>>, 8);
+ assert_size!(Option<NoNiche<N32>>, 8); // (✗ niche opt)
- assert_eq!(Option<UnsafeCell<u32>>, 8);
- assert_eq!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
+ assert_size!(Option<UnsafeCell<u32>>, 8);
+ assert_size!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
- assert_eq!( UnsafeCell<&()> , 8);
- assert_eq!(Option<UnsafeCell<&()>>, 16); // (✗ niche opt)
- assert_eq!( Cell<&()> , 8);
- assert_eq!(Option< Cell<&()>>, 16); // (✗ niche opt)
- assert_eq!( RefCell<&()> , 16);
- assert_eq!(Option< RefCell<&()>>, 24); // (✗ niche opt)
- assert_eq!( RwLock<&()> , 24);
- assert_eq!(Option< RwLock<&()>>, 32); // (✗ niche opt)
- assert_eq!( Mutex<&()> , 16);
- assert_eq!(Option< Mutex<&()>>, 24); // (✗ niche opt)
+ assert_size!( UnsafeCell<&()> , 8);
+ assert_size!(Option<UnsafeCell<&()>>, 16); // (✗ niche opt)
+ assert_size!( Cell<&()> , 8);
+ assert_size!(Option< Cell<&()>>, 16); // (✗ niche opt)
+ assert_size!( RefCell<&()> , 16);
+ assert_size!(Option< RefCell<&()>>, 24); // (✗ niche opt)
+ assert_size!( RwLock<&()> , 24);
+ assert_size!(Option< RwLock<&()>>, 32); // (✗ niche opt)
+ assert_size!( Mutex<&()> , 16);
+ assert_size!(Option< Mutex<&()>>, 24); // (✗ niche opt)
- assert_eq!( UnsafeCell<&[i32]> , 16);
- assert_eq!(Option<UnsafeCell<&[i32]>>, 24); // (✗ niche opt)
- assert_eq!( UnsafeCell<(&(), &())> , 16);
- assert_eq!(Option<UnsafeCell<(&(), &())>>, 24); // (✗ niche opt)
+ assert_size!( UnsafeCell<&[i32]> , 16);
+ assert_size!(Option<UnsafeCell<&[i32]>>, 24); // (✗ niche opt)
+ assert_size!( UnsafeCell<(&(), &())> , 16);
+ assert_size!(Option<UnsafeCell<(&(), &())>>, 24); // (✗ niche opt)
trait Trait {}
- assert_eq!( UnsafeCell<&dyn Trait> , 16);
- assert_eq!(Option<UnsafeCell<&dyn Trait>>, 24); // (✗ niche opt)
+ assert_size!( UnsafeCell<&dyn Trait> , 16);
+ assert_size!(Option<UnsafeCell<&dyn Trait>>, 24); // (✗ niche opt)
#[repr(simd)]
pub struct Vec4<T>([T; 4]);
- assert_eq!( UnsafeCell<Vec4<N32>> , 16);
- assert_eq!(Option<UnsafeCell<Vec4<N32>>>, 32); // (✗ niche opt)
+ assert_size!( UnsafeCell<Vec4<N32>> , 16);
+ assert_size!(Option<UnsafeCell<Vec4<N32>>>, 32); // (✗ niche opt)
}
From 9a204509d2fe9d0ea72cb79ed6e341de7a3bcacb Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:34:01 +0000
Subject: [PATCH 10/19] Show sizes in error output
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 7fb55d8219ef8..21ff0cb1e5527 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -18,10 +18,12 @@ struct Transparent<T>(T);
struct NoNiche<T>(UnsafeCell<T>);
+struct Size<const S: usize>;
+
// Overwriting the runtime assertion and making it a compile-time assertion
macro_rules! assert_size {
($a:ty, $b:literal) => {{
- const _: () = assert!(std::mem::size_of::<$a>() == $b);
+ const _: Size::<$b> = Size::<{std::mem::size_of::<$a>()}>;
}};
}
From fcd7207d0e5ab4a9598e3b6caf6248134e5f95d6 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 10:43:47 +0000
Subject: [PATCH 11/19] Make tests work on 32 bit and 64 bit
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 41 ++++++++++---------
1 file changed, 22 insertions(+), 19 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 21ff0cb1e5527..2833f49a27bf6 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -8,6 +8,7 @@
#![feature(repr_simd)]
use std::cell::{UnsafeCell, RefCell, Cell};
+use std::mem::size_of;
use std::num::NonZeroU32 as N32;
use std::sync::{Mutex, RwLock};
@@ -22,11 +23,13 @@ struct Size<const S: usize>;
// Overwriting the runtime assertion and making it a compile-time assertion
macro_rules! assert_size {
- ($a:ty, $b:literal) => {{
- const _: Size::<$b> = Size::<{std::mem::size_of::<$a>()}>;
+ ($a:ty, $b:expr) => {{
+ const _: Size::<{$b}> = Size::<{size_of::<$a>()}>;
}};
}
+const PTR_SIZE: usize = std::mem::size_of::<*const ()>();
+
fn main() {
assert_size!(Option<Wrapper<u32>>, 8);
assert_size!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
@@ -38,25 +41,25 @@ fn main() {
assert_size!(Option<UnsafeCell<u32>>, 8);
assert_size!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
- assert_size!( UnsafeCell<&()> , 8);
- assert_size!(Option<UnsafeCell<&()>>, 16); // (✗ niche opt)
- assert_size!( Cell<&()> , 8);
- assert_size!(Option< Cell<&()>>, 16); // (✗ niche opt)
- assert_size!( RefCell<&()> , 16);
- assert_size!(Option< RefCell<&()>>, 24); // (✗ niche opt)
- assert_size!( RwLock<&()> , 24);
- assert_size!(Option< RwLock<&()>>, 32); // (✗ niche opt)
- assert_size!( Mutex<&()> , 16);
- assert_size!(Option< Mutex<&()>>, 24); // (✗ niche opt)
-
- assert_size!( UnsafeCell<&[i32]> , 16);
- assert_size!(Option<UnsafeCell<&[i32]>>, 24); // (✗ niche opt)
- assert_size!( UnsafeCell<(&(), &())> , 16);
- assert_size!(Option<UnsafeCell<(&(), &())>>, 24); // (✗ niche opt)
+ assert_size!( UnsafeCell<&()> , PTR_SIZE);
+ assert_size!(Option<UnsafeCell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
+ assert_size!( Cell<&()> , PTR_SIZE);
+ assert_size!(Option< Cell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
+ assert_size!( RefCell<&()> , PTR_SIZE * 2);
+ assert_size!(Option< RefCell<&()>>, PTR_SIZE * 3); // (✗ niche opt)
+ assert_size!( RwLock<&()> , if cfg!(target_pointer_width = "32") { 16 } else { 24 });
+ assert_size!(Option< RwLock<&()>>, if cfg!(target_pointer_width = "32") { 20 } else { 32 }); // (✗ niche opt)
+ assert_size!( Mutex<&()> , if cfg!(target_pointer_width = "32") { 12 } else { 16 });
+ assert_size!(Option< Mutex<&()>>, if cfg!(target_pointer_width = "32") { 16 } else { 24 }); // (✗ niche opt)
+
+ assert_size!( UnsafeCell<&[i32]> , PTR_SIZE * 2);
+ assert_size!(Option<UnsafeCell<&[i32]>>, PTR_SIZE * 3); // (✗ niche opt)
+ assert_size!( UnsafeCell<(&(), &())> , PTR_SIZE * 2);
+ assert_size!(Option<UnsafeCell<(&(), &())>>, PTR_SIZE * 3); // (✗ niche opt)
trait Trait {}
- assert_size!( UnsafeCell<&dyn Trait> , 16);
- assert_size!(Option<UnsafeCell<&dyn Trait>>, 24); // (✗ niche opt)
+ assert_size!( UnsafeCell<&dyn Trait> , PTR_SIZE * 2);
+ assert_size!(Option<UnsafeCell<&dyn Trait>>, PTR_SIZE * 3); // (✗ niche opt)
#[repr(simd)]
pub struct Vec4<T>([T; 4]);
From 8440208eb13ec1f680592b9a7793a67f2b1be15e Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 11:07:03 +0000
Subject: [PATCH 12/19] tidy
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 20 +++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 2833f49a27bf6..1d0e1fce178d0 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -47,10 +47,22 @@ fn main() {
assert_size!(Option< Cell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
assert_size!( RefCell<&()> , PTR_SIZE * 2);
assert_size!(Option< RefCell<&()>>, PTR_SIZE * 3); // (✗ niche opt)
- assert_size!( RwLock<&()> , if cfg!(target_pointer_width = "32") { 16 } else { 24 });
- assert_size!(Option< RwLock<&()>>, if cfg!(target_pointer_width = "32") { 20 } else { 32 }); // (✗ niche opt)
- assert_size!( Mutex<&()> , if cfg!(target_pointer_width = "32") { 12 } else { 16 });
- assert_size!(Option< Mutex<&()>>, if cfg!(target_pointer_width = "32") { 16 } else { 24 }); // (✗ niche opt)
+ assert_size!(
+ RwLock<&()>,
+ if cfg!(target_pointer_width = "32") { 16 } else { 24 }
+ );
+ assert_size!(
+ Option<RwLock<&()>>,
+ if cfg!(target_pointer_width = "32") { 20 } else { 32 }
+ ); // (✗ niche opt)
+ assert_size!(
+ Mutex<&()> ,
+ if cfg!(target_pointer_width = "32") { 12 } else { 16 }
+ );
+ assert_size!(
+ Option<Mutex<&()>>,
+ if cfg!(target_pointer_width = "32") { 16 } else { 24 }
+ ); // (✗ niche opt)
assert_size!( UnsafeCell<&[i32]> , PTR_SIZE * 2);
assert_size!(Option<UnsafeCell<&[i32]>>, PTR_SIZE * 3); // (✗ niche opt)
From d935c70afa464dcf16db532e39ae53621debd096 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 14:16:14 +0000
Subject: [PATCH 13/19] Don't allow accidental runtime-checks
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 101 +++++++++---------
1 file changed, 50 insertions(+), 51 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 1d0e1fce178d0..865fc2ae29702 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -4,6 +4,7 @@
// size in memory as an `Option<UnsafeCell<u32>>` (namely, 8 bytes).
// check-pass
+// compile-flags: --crate-type=lib
#![feature(repr_simd)]
@@ -23,59 +24,57 @@ struct Size<const S: usize>;
// Overwriting the runtime assertion and making it a compile-time assertion
macro_rules! assert_size {
- ($a:ty, $b:expr) => {{
+ ($a:ty, $b:expr) => {
const _: Size::<{$b}> = Size::<{size_of::<$a>()}>;
- }};
+ };
}
const PTR_SIZE: usize = std::mem::size_of::<*const ()>();
-fn main() {
- assert_size!(Option<Wrapper<u32>>, 8);
- assert_size!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
- assert_size!(Option<Transparent<u32>>, 8);
- assert_size!(Option<Transparent<N32>>, 4); // (✓ niche opt)
- assert_size!(Option<NoNiche<u32>>, 8);
- assert_size!(Option<NoNiche<N32>>, 8); // (✗ niche opt)
-
- assert_size!(Option<UnsafeCell<u32>>, 8);
- assert_size!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
-
- assert_size!( UnsafeCell<&()> , PTR_SIZE);
- assert_size!(Option<UnsafeCell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
- assert_size!( Cell<&()> , PTR_SIZE);
- assert_size!(Option< Cell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
- assert_size!( RefCell<&()> , PTR_SIZE * 2);
- assert_size!(Option< RefCell<&()>>, PTR_SIZE * 3); // (✗ niche opt)
- assert_size!(
- RwLock<&()>,
- if cfg!(target_pointer_width = "32") { 16 } else { 24 }
- );
- assert_size!(
- Option<RwLock<&()>>,
- if cfg!(target_pointer_width = "32") { 20 } else { 32 }
- ); // (✗ niche opt)
- assert_size!(
- Mutex<&()> ,
- if cfg!(target_pointer_width = "32") { 12 } else { 16 }
- );
- assert_size!(
- Option<Mutex<&()>>,
- if cfg!(target_pointer_width = "32") { 16 } else { 24 }
- ); // (✗ niche opt)
-
- assert_size!( UnsafeCell<&[i32]> , PTR_SIZE * 2);
- assert_size!(Option<UnsafeCell<&[i32]>>, PTR_SIZE * 3); // (✗ niche opt)
- assert_size!( UnsafeCell<(&(), &())> , PTR_SIZE * 2);
- assert_size!(Option<UnsafeCell<(&(), &())>>, PTR_SIZE * 3); // (✗ niche opt)
-
- trait Trait {}
- assert_size!( UnsafeCell<&dyn Trait> , PTR_SIZE * 2);
- assert_size!(Option<UnsafeCell<&dyn Trait>>, PTR_SIZE * 3); // (✗ niche opt)
-
- #[repr(simd)]
- pub struct Vec4<T>([T; 4]);
-
- assert_size!( UnsafeCell<Vec4<N32>> , 16);
- assert_size!(Option<UnsafeCell<Vec4<N32>>>, 32); // (✗ niche opt)
-}
+assert_size!(Option<Wrapper<u32>>, 8);
+assert_size!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
+assert_size!(Option<Transparent<u32>>, 8);
+assert_size!(Option<Transparent<N32>>, 4); // (✓ niche opt)
+assert_size!(Option<NoNiche<u32>>, 8);
+assert_size!(Option<NoNiche<N32>>, 8); // (✗ niche opt)
+
+assert_size!(Option<UnsafeCell<u32>>, 8);
+assert_size!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
+
+assert_size!( UnsafeCell<&()> , PTR_SIZE);
+assert_size!(Option<UnsafeCell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
+assert_size!( Cell<&()> , PTR_SIZE);
+assert_size!(Option< Cell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
+assert_size!( RefCell<&()> , PTR_SIZE * 2);
+assert_size!(Option< RefCell<&()>>, PTR_SIZE * 3); // (✗ niche opt)
+assert_size!(
+ RwLock<&()>,
+ if cfg!(target_pointer_width = "32") { 16 } else { 24 }
+);
+assert_size!(
+ Option<RwLock<&()>>,
+ if cfg!(target_pointer_width = "32") { 20 } else { 32 }
+); // (✗ niche opt)
+assert_size!(
+ Mutex<&()> ,
+ if cfg!(target_pointer_width = "32") { 12 } else { 16 }
+);
+assert_size!(
+ Option<Mutex<&()>>,
+ if cfg!(target_pointer_width = "32") { 16 } else { 24 }
+); // (✗ niche opt)
+
+assert_size!( UnsafeCell<&[i32]> , PTR_SIZE * 2);
+assert_size!(Option<UnsafeCell<&[i32]>>, PTR_SIZE * 3); // (✗ niche opt)
+assert_size!( UnsafeCell<(&(), &())> , PTR_SIZE * 2);
+assert_size!(Option<UnsafeCell<(&(), &())>>, PTR_SIZE * 3); // (✗ niche opt)
+
+trait Trait {}
+assert_size!( UnsafeCell<&dyn Trait> , PTR_SIZE * 2);
+assert_size!(Option<UnsafeCell<&dyn Trait>>, PTR_SIZE * 3); // (✗ niche opt)
+
+#[repr(simd)]
+pub struct Vec4<T>([T; 4]);
+
+assert_size!( UnsafeCell<Vec4<N32>> , 16);
+assert_size!(Option<UnsafeCell<Vec4<N32>>>, 32); // (✗ niche opt)
From cdd6bba8f662b25d52a58d5ffebbe5c3eac60220 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 14:23:32 +0000
Subject: [PATCH 14/19] Simplify size checking
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 70 ++++++++-----------
1 file changed, 31 insertions(+), 39 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 865fc2ae29702..9e80a708f2fd7 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -23,58 +23,50 @@ struct NoNiche<T>(UnsafeCell<T>);
struct Size<const S: usize>;
// Overwriting the runtime assertion and making it a compile-time assertion
-macro_rules! assert_size {
- ($a:ty, $b:expr) => {
- const _: Size::<{$b}> = Size::<{size_of::<$a>()}>;
+macro_rules! assert_size_eq {
+ ($ty:ty, $size:expr) => {
+ const _: Size::<{$size}> = Size::<{size_of::<$ty>()}>;
+ };
+ ($ty:ty, $size:expr, $optioned_size:expr) => {
+ assert_size_eq!($ty, $size);
+ assert_size_eq!(Option<$ty>, $optioned_size);
+ const _: () = assert!($size == $optioned_size || size_of::<$ty>() < size_of::<Option<$ty>>());
};
}
const PTR_SIZE: usize = std::mem::size_of::<*const ()>();
-assert_size!(Option<Wrapper<u32>>, 8);
-assert_size!(Option<Wrapper<N32>>, 4); // (✓ niche opt)
-assert_size!(Option<Transparent<u32>>, 8);
-assert_size!(Option<Transparent<N32>>, 4); // (✓ niche opt)
-assert_size!(Option<NoNiche<u32>>, 8);
-assert_size!(Option<NoNiche<N32>>, 8); // (✗ niche opt)
-
-assert_size!(Option<UnsafeCell<u32>>, 8);
-assert_size!(Option<UnsafeCell<N32>>, 8); // (✗ niche opt)
-
-assert_size!( UnsafeCell<&()> , PTR_SIZE);
-assert_size!(Option<UnsafeCell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
-assert_size!( Cell<&()> , PTR_SIZE);
-assert_size!(Option< Cell<&()>>, PTR_SIZE * 2); // (✗ niche opt)
-assert_size!( RefCell<&()> , PTR_SIZE * 2);
-assert_size!(Option< RefCell<&()>>, PTR_SIZE * 3); // (✗ niche opt)
-assert_size!(
+assert_size_eq!(Wrapper<u32>, 4, 8);
+assert_size_eq!(Wrapper<N32>, 4, 4); // (✓ niche opt)
+assert_size_eq!(Transparent<u32>, 4, 8);
+assert_size_eq!(Transparent<N32>, 4, 4); // (✓ niche opt)
+assert_size_eq!(NoNiche<u32>, 4, 8);
+assert_size_eq!(NoNiche<N32>, 4, 8);
+
+assert_size_eq!(UnsafeCell<u32>, 4, 8);
+assert_size_eq!(UnsafeCell<N32>, 4, 8);
+
+assert_size_eq!(UnsafeCell<&()> , PTR_SIZE, PTR_SIZE * 2);
+assert_size_eq!( Cell<&()> , PTR_SIZE, PTR_SIZE * 2);
+assert_size_eq!( RefCell<&()> , PTR_SIZE * 2, PTR_SIZE * 3);
+assert_size_eq!(
RwLock<&()>,
- if cfg!(target_pointer_width = "32") { 16 } else { 24 }
-);
-assert_size!(
- Option<RwLock<&()>>,
+ if cfg!(target_pointer_width = "32") { 16 } else { 24 },
if cfg!(target_pointer_width = "32") { 20 } else { 32 }
-); // (✗ niche opt)
-assert_size!(
- Mutex<&()> ,
- if cfg!(target_pointer_width = "32") { 12 } else { 16 }
);
-assert_size!(
- Option<Mutex<&()>>,
+assert_size_eq!(
+ Mutex<&()> ,
+ if cfg!(target_pointer_width = "32") { 12 } else { 16 },
if cfg!(target_pointer_width = "32") { 16 } else { 24 }
-); // (✗ niche opt)
+);
-assert_size!( UnsafeCell<&[i32]> , PTR_SIZE * 2);
-assert_size!(Option<UnsafeCell<&[i32]>>, PTR_SIZE * 3); // (✗ niche opt)
-assert_size!( UnsafeCell<(&(), &())> , PTR_SIZE * 2);
-assert_size!(Option<UnsafeCell<(&(), &())>>, PTR_SIZE * 3); // (✗ niche opt)
+assert_size_eq!(UnsafeCell<&[i32]> , PTR_SIZE * 2, PTR_SIZE * 3);
+assert_size_eq!(UnsafeCell<(&(), &())> , PTR_SIZE * 2, PTR_SIZE * 3);
trait Trait {}
-assert_size!( UnsafeCell<&dyn Trait> , PTR_SIZE * 2);
-assert_size!(Option<UnsafeCell<&dyn Trait>>, PTR_SIZE * 3); // (✗ niche opt)
+assert_size_eq!(UnsafeCell<&dyn Trait> , PTR_SIZE * 2, PTR_SIZE * 3);
#[repr(simd)]
pub struct Vec4<T>([T; 4]);
-assert_size!( UnsafeCell<Vec4<N32>> , 16);
-assert_size!(Option<UnsafeCell<Vec4<N32>>>, 32); // (✗ niche opt)
+assert_size_eq!(UnsafeCell<Vec4<N32>> , 16, 32);
From 0318b70514e13d09fd0e9043da4b7c49e0285f75 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 14:35:04 +0000
Subject: [PATCH 15/19] tidy
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 9e80a708f2fd7..7f159887ba1d4 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -30,7 +30,10 @@ macro_rules! assert_size_eq {
($ty:ty, $size:expr, $optioned_size:expr) => {
assert_size_eq!($ty, $size);
assert_size_eq!(Option<$ty>, $optioned_size);
- const _: () = assert!($size == $optioned_size || size_of::<$ty>() < size_of::<Option<$ty>>());
+ const _: () = assert!(
+ $size == $optioned_size ||
+ size_of::<$ty>() < size_of::<Option<$ty>>()
+ );
};
}
From 3338593afd6a010a2ce6799d3bf4bf4c2a252950 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 11 Jul 2022 15:41:38 +0000
Subject: [PATCH 16/19] Only check relative sizes on platform specific types
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 69 +++++++++----------
1 file changed, 32 insertions(+), 37 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 7f159887ba1d4..9eed2ad361ce3 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -22,54 +22,49 @@ struct NoNiche<T>(UnsafeCell<T>);
struct Size<const S: usize>;
-// Overwriting the runtime assertion and making it a compile-time assertion
-macro_rules! assert_size_eq {
- ($ty:ty, $size:expr) => {
+macro_rules! check_sizes {
+ (check_one_specific_size: $ty:ty, $size:expr) => {
const _: Size::<{$size}> = Size::<{size_of::<$ty>()}>;
};
($ty:ty, $size:expr, $optioned_size:expr) => {
- assert_size_eq!($ty, $size);
- assert_size_eq!(Option<$ty>, $optioned_size);
- const _: () = assert!(
- $size == $optioned_size ||
- size_of::<$ty>() < size_of::<Option<$ty>>()
- );
+ check_sizes!(check_one_specific_size: $ty, $size);
+ check_sizes!(check_one_specific_size: Option<$ty>, $optioned_size);
+ check_sizes!(check_no_niche_opt: $size != $optioned_size, $ty);
+ };
+ ($ty:ty) => {
+ check_sizes!(check_no_niche_opt: true, $ty);
+ };
+ (check_no_niche_opt: $no_niche_opt:expr, $ty:ty) => {
+ const _: () = if $no_niche_opt { assert!(size_of::<$ty>() < size_of::<Option<$ty>>()); };
};
}
const PTR_SIZE: usize = std::mem::size_of::<*const ()>();
-assert_size_eq!(Wrapper<u32>, 4, 8);
-assert_size_eq!(Wrapper<N32>, 4, 4); // (✓ niche opt)
-assert_size_eq!(Transparent<u32>, 4, 8);
-assert_size_eq!(Transparent<N32>, 4, 4); // (✓ niche opt)
-assert_size_eq!(NoNiche<u32>, 4, 8);
-assert_size_eq!(NoNiche<N32>, 4, 8);
-
-assert_size_eq!(UnsafeCell<u32>, 4, 8);
-assert_size_eq!(UnsafeCell<N32>, 4, 8);
-
-assert_size_eq!(UnsafeCell<&()> , PTR_SIZE, PTR_SIZE * 2);
-assert_size_eq!( Cell<&()> , PTR_SIZE, PTR_SIZE * 2);
-assert_size_eq!( RefCell<&()> , PTR_SIZE * 2, PTR_SIZE * 3);
-assert_size_eq!(
- RwLock<&()>,
- if cfg!(target_pointer_width = "32") { 16 } else { 24 },
- if cfg!(target_pointer_width = "32") { 20 } else { 32 }
-);
-assert_size_eq!(
- Mutex<&()> ,
- if cfg!(target_pointer_width = "32") { 12 } else { 16 },
- if cfg!(target_pointer_width = "32") { 16 } else { 24 }
-);
-
-assert_size_eq!(UnsafeCell<&[i32]> , PTR_SIZE * 2, PTR_SIZE * 3);
-assert_size_eq!(UnsafeCell<(&(), &())> , PTR_SIZE * 2, PTR_SIZE * 3);
+check_sizes!(Wrapper<u32>, 4, 8);
+check_sizes!(Wrapper<N32>, 4, 4); // (✓ niche opt)
+check_sizes!(Transparent<u32>, 4, 8);
+check_sizes!(Transparent<N32>, 4, 4); // (✓ niche opt)
+check_sizes!(NoNiche<u32>, 4, 8);
+check_sizes!(NoNiche<N32>, 4, 8);
+
+check_sizes!(UnsafeCell<u32>, 4, 8);
+check_sizes!(UnsafeCell<N32>, 4, 8);
+
+check_sizes!(UnsafeCell<&()> , PTR_SIZE, PTR_SIZE * 2);
+check_sizes!( Cell<&()> , PTR_SIZE, PTR_SIZE * 2);
+check_sizes!( RefCell<&()> , PTR_SIZE * 2, PTR_SIZE * 3);
+
+check_sizes!(RwLock<&()>);
+check_sizes!(Mutex<&()>);
+
+check_sizes!(UnsafeCell<&[i32]> , PTR_SIZE * 2, PTR_SIZE * 3);
+check_sizes!(UnsafeCell<(&(), &())> , PTR_SIZE * 2, PTR_SIZE * 3);
trait Trait {}
-assert_size_eq!(UnsafeCell<&dyn Trait> , PTR_SIZE * 2, PTR_SIZE * 3);
+check_sizes!(UnsafeCell<&dyn Trait> , PTR_SIZE * 2, PTR_SIZE * 3);
#[repr(simd)]
pub struct Vec4<T>([T; 4]);
-assert_size_eq!(UnsafeCell<Vec4<N32>> , 16, 32);
+check_sizes!(UnsafeCell<Vec4<N32>> , 16, 32);
From 24e87965ae35843fe340a5104482be1d1f827af7 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Tue, 12 Jul 2022 07:22:52 +0000
Subject: [PATCH 17/19] Use some more visible sigils than `,`
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 32 +++++++++----------
1 file changed, 16 insertions(+), 16 deletions(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index 9eed2ad361ce3..e82eaa38612cd 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -26,7 +26,7 @@ macro_rules! check_sizes {
(check_one_specific_size: $ty:ty, $size:expr) => {
const _: Size::<{$size}> = Size::<{size_of::<$ty>()}>;
};
- ($ty:ty, $size:expr, $optioned_size:expr) => {
+ ($ty:ty: $size:expr => $optioned_size:expr) => {
check_sizes!(check_one_specific_size: $ty, $size);
check_sizes!(check_one_specific_size: Option<$ty>, $optioned_size);
check_sizes!(check_no_niche_opt: $size != $optioned_size, $ty);
@@ -41,30 +41,30 @@ macro_rules! check_sizes {
const PTR_SIZE: usize = std::mem::size_of::<*const ()>();
-check_sizes!(Wrapper<u32>, 4, 8);
-check_sizes!(Wrapper<N32>, 4, 4); // (✓ niche opt)
-check_sizes!(Transparent<u32>, 4, 8);
-check_sizes!(Transparent<N32>, 4, 4); // (✓ niche opt)
-check_sizes!(NoNiche<u32>, 4, 8);
-check_sizes!(NoNiche<N32>, 4, 8);
+check_sizes!(Wrapper<u32>: 4 => 8);
+check_sizes!(Wrapper<N32>: 4 => 4); // (✓ niche opt)
+check_sizes!(Transparent<u32>: 4 => 8);
+check_sizes!(Transparent<N32>: 4 => 4); // (✓ niche opt)
+check_sizes!(NoNiche<u32>: 4 => 8);
+check_sizes!(NoNiche<N32>: 4 => 8);
-check_sizes!(UnsafeCell<u32>, 4, 8);
-check_sizes!(UnsafeCell<N32>, 4, 8);
+check_sizes!(UnsafeCell<u32>: 4 => 8);
+check_sizes!(UnsafeCell<N32>: 4 => 8);
-check_sizes!(UnsafeCell<&()> , PTR_SIZE, PTR_SIZE * 2);
-check_sizes!( Cell<&()> , PTR_SIZE, PTR_SIZE * 2);
-check_sizes!( RefCell<&()> , PTR_SIZE * 2, PTR_SIZE * 3);
+check_sizes!(UnsafeCell<&()>: PTR_SIZE => PTR_SIZE * 2);
+check_sizes!( Cell<&()>: PTR_SIZE => PTR_SIZE * 2);
+check_sizes!( RefCell<&()>: PTR_SIZE * 2 => PTR_SIZE * 3);
check_sizes!(RwLock<&()>);
check_sizes!(Mutex<&()>);
-check_sizes!(UnsafeCell<&[i32]> , PTR_SIZE * 2, PTR_SIZE * 3);
-check_sizes!(UnsafeCell<(&(), &())> , PTR_SIZE * 2, PTR_SIZE * 3);
+check_sizes!(UnsafeCell<&[i32]>: PTR_SIZE * 2 => PTR_SIZE * 3);
+check_sizes!(UnsafeCell<(&(), &())>: PTR_SIZE * 2 => PTR_SIZE * 3);
trait Trait {}
-check_sizes!(UnsafeCell<&dyn Trait> , PTR_SIZE * 2, PTR_SIZE * 3);
+check_sizes!(UnsafeCell<&dyn Trait>: PTR_SIZE * 2 => PTR_SIZE * 3);
#[repr(simd)]
pub struct Vec4<T>([T; 4]);
-check_sizes!(UnsafeCell<Vec4<N32>> , 16, 32);
+check_sizes!(UnsafeCell<Vec4<N32>>: 16 => 32);
From 726919629e0ca3660a41843f9565469e5dd2b2d9 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Tue, 12 Jul 2022 07:29:36 +0000
Subject: [PATCH 18/19] Always check Cell alongside with `UnsafeCell`
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index e82eaa38612cd..fce101d7bb173 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -26,11 +26,23 @@ macro_rules! check_sizes {
(check_one_specific_size: $ty:ty, $size:expr) => {
const _: Size::<{$size}> = Size::<{size_of::<$ty>()}>;
};
+ // Any tests run on `UnsafeCell` must be the same for `Cell`
+ (UnsafeCell<$ty:ty>: $size:expr => $optioned_size:expr) => {
+ check_sizes!(Cell<$ty>: $size => $optioned_size);
+ check_sizes!(@actual_check: UnsafeCell<$ty>: $size => $optioned_size);
+ };
($ty:ty: $size:expr => $optioned_size:expr) => {
+ check_sizes!(@actual_check: $ty: $size => $optioned_size);
+ };
+ // This branch does the actual checking logic, the `@actual_check` prefix is here to distinguish
+ // it from other branches and not accidentally match any.
+ (@actual_check: $ty:ty: $size:expr => $optioned_size:expr) => {
check_sizes!(check_one_specific_size: $ty, $size);
check_sizes!(check_one_specific_size: Option<$ty>, $optioned_size);
check_sizes!(check_no_niche_opt: $size != $optioned_size, $ty);
};
+ // only check that there is no niche (size goes up when wrapped in an option),
+ // don't check actual sizes
($ty:ty) => {
check_sizes!(check_no_niche_opt: true, $ty);
};
@@ -52,7 +64,6 @@ check_sizes!(UnsafeCell<u32>: 4 => 8);
check_sizes!(UnsafeCell<N32>: 4 => 8);
check_sizes!(UnsafeCell<&()>: PTR_SIZE => PTR_SIZE * 2);
-check_sizes!( Cell<&()>: PTR_SIZE => PTR_SIZE * 2);
check_sizes!( RefCell<&()>: PTR_SIZE * 2 => PTR_SIZE * 3);
check_sizes!(RwLock<&()>);
From 519c07b3ce7f34975aacbe128e55d84411348229 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Wed, 13 Jul 2022 10:11:35 +0000
Subject: [PATCH 19/19] Limit test to x86 targets for reproducability
---
src/test/ui/layout/unsafe-cell-hides-niche.rs | 1 +
1 file changed, 1 insertion(+)
diff --git a/src/test/ui/layout/unsafe-cell-hides-niche.rs b/src/test/ui/layout/unsafe-cell-hides-niche.rs
index fce101d7bb173..73b32066fadcd 100644
--- a/src/test/ui/layout/unsafe-cell-hides-niche.rs
+++ b/src/test/ui/layout/unsafe-cell-hides-niche.rs
@@ -5,6 +5,7 @@
// check-pass
// compile-flags: --crate-type=lib
+// only-x86
#![feature(repr_simd)]