That's more consistent with InterpResult and InterpError.

Normalization can leave some type-vars unresolved in its return type.
Make sure to resolve them so we have an infcx-independent type that can
be used with `needs_drop`.

Fixes rust-lang#61402.

This also adds assertions that the operations work as expected.

Unreserve `macro_rules` as a macro name

No behavior change, just flatter and simpler code

… terms of DoubleEndedIterator::next_back for types in liballoc and libcore.

Provided that the iterator has finite length and does not trigger user-provided code, this is safe.

What follows is a full list of the DoubleEndedIterators in liballoc/libcore and whether this optimization is safe, and if not, why not.

src/liballoc/boxed.rs
Box: Pass through to avoid defeating optimization of the underlying DoubleIterator implementation. This has no correctness impact.

src/liballoc/collections/binary_heap.rs
Iter: Pass through to avoid defeating optimizations on slice::Iter
IntoIter: Not safe, changes Drop order
Drain: Not safe, changes Drop order

src/liballoc/collections/btree/map.rs
Iter: Safe to call next_back, invokes no user defined code.
IterMut: ditto
IntoIter: Not safe, changes Drop order
Keys: Safe to call next_back, invokes no user defined code.
Values: ditto
ValuesMut: ditto
Range: ditto
RangeMut: ditto

src/liballoc/collections/btree/set.rs
Iter: Safe to call next_back, invokes no user defined code.
IntoIter: Not safe, changes Drop order
Range: Safe to call next_back, invokes no user defined code.

src/liballoc/collections/linked_list.rs
Iter: Safe to call next_back, invokes no user defined code.
IterMut: ditto
IntoIter: Not safe, changes Drop order

src/liballoc/collections/vec_deque.rs
Iter: Safe to call next_back, invokes no user defined code.
IterMut: ditto
IntoIter: Not safe, changes Drop order
Drain: ditto

src/liballoc/string.rs
Drain: Safe because return type is a primitive (char)

src/liballoc/vec.rs
IntoIter: Not safe, changes Drop order
Drain: ditto
Splice: ditto

src/libcore/ascii.rs
EscapeDefault: Safe because return type is a primitive (u8)

src/libcore/iter/adapters/chain.rs
Chain: Not safe, invokes user defined code (Iterator impl)

src/libcore/iter/adapters/flatten.rs
FlatMap: Not safe, invokes user defined code (Iterator impl)
Flatten: ditto
FlattenCompat: ditto

src/libcore/iter/adapters/mod.rs
Rev: Not safe, invokes user defined code (Iterator impl)
Copied: ditto
Cloned: Not safe, invokes user defined code (Iterator impl and T::clone)
Map: Not safe, invokes user defined code (Iterator impl + closure)
Filter: ditto
FilterMap: ditto
Enumerate: Not safe, invokes user defined code (Iterator impl)
Skip: ditto
Fuse: ditto
Inspect: ditto

src/libcore/iter/adapters/zip.rs
Zip: Not safe, invokes user defined code (Iterator impl)

src/libcore/iter/range.rs
ops::Range: Not safe, changes Drop order, but ALREADY HAS SPECIALIZATION
ops::RangeInclusive: ditto

src/libcore/iter/sources.rs
Repeat: Not safe, calling last should iloop.
Empty: No point, iterator is at most one item long.
Once: ditto
OnceWith: ditto

src/libcore/option.rs
Item: No point, iterator is at most one item long.
Iter: ditto
IterMut: ditto
IntoIter: ditto

src/libcore/result.rs
Iter: No point, iterator is at most one item long
IterMut: ditto
IntoIter: ditto

src/libcore/slice/mod.rs
Split: Not safe, invokes user defined closure
SplitMut: ditto
RSplit: ditto
RSplitMut: ditto
Windows: Safe, already has specialization
Chunks: ditto
ChunksMut: ditto
ChunksExact: ditto
ChunksExactMut: ditto
RChunks: ditto
RChunksMut: ditto
RChunksExact: ditto
RChunksExactMut: ditto

src/libcore/str/mod.rs
Chars: Safe, already has specialization
CharIndices: ditto
Bytes: ditto
Lines: Safe to call next_back, invokes no user defined code.
LinesAny: Deprecated
Everything that is generic over P: Pattern: Not safe because Pattern invokes user defined code.
SplitWhitespace: Safe to call next_back, invokes no user defined code.
SplitAsciiWhitespace: ditto

When llvm-libunwind feature is enabled, we need to use link attribute on
extern "C" blocks to make sure that symbols provided by LLVM's libunwind
that's built as part of Rust's libunwind crate are re-exported.

This addresses issue rust-lang#62088.

Moved to its own PR

…eddyb

Remove needless lifetimes (rustc)

rename InterpretCx -> InterpCx

That's more consistent with InterpResult and InterpError.

r? @oli-obk

wfcheck: resolve the type-vars in `AdtField` types

Normalization can leave some type-vars unresolved in its return type.
Make sure to resolve them so we have an infcx-independent type that can
be used with `needs_drop`.

Fixes rust-lang#61402.

Closes rust-lang#62212 - this PR fixes the root cause.

…place-default, r=dtolnay,Centril

Use mem::take instead of mem::replace with default

…mple, r=dtolnay

Update mem::replace example to not be identical to mem::take

This also adds assertions that the operations work as expected.

syntax: Unsupport `foo! bar { ... }` macros in the parser

Their support in expansion was removed in rust-lang#61606.

Also un-reserve `macro_rules` as a macro name, there's no ambiguity between `macro_rules` definitions and macro calls (it also wasn't reserved correctly).

cc rust-lang/wg-grammar#51

Clean up inherent_impls

Split out from rust-lang#61923.

r? @eddyb

… r=tmandry

Use link attributes on extern "C" blocks with llvm-libuwind

When llvm-libunwind feature is enabled, we need to use link attribute on
extern "C" blocks to make sure that symbols provided by LLVM's libunwind
that's built as part of Rust's libunwind crate are re-exported.

This addresses issue rust-lang#62088.

miri realloc: do not require giving old size+align

refactor check_for_substitution

No behavior change, just flatter and simpler code.

r? @petrochenkov

When possible without changing semantics, implement Iterator::last in terms of DoubleEndedIterator::next_back for types in liballoc and libcore.

Provided that the iterator has finite length and does not trigger user-provided code, this is safe.

What follows is a full list of the DoubleEndedIterators in liballoc/libcore and whether this optimization is safe, and if not, why not.

src/liballoc/boxed.rs
Box: Pass through to avoid defeating optimization of the underlying DoubleIterator implementation. This has no correctness impact.

src/liballoc/collections/binary_heap.rs
Iter: Pass through to avoid defeating optimizations on slice::Iter
IntoIter: Not safe, changes Drop order
Drain: Not safe, changes Drop order

src/liballoc/collections/btree/map.rs
Iter: Safe to call next_back, invokes no user defined code.
IterMut: ditto
IntoIter: Not safe, changes Drop order
Keys: Safe to call next_back, invokes no user defined code.
Values: ditto
ValuesMut: ditto
Range: ditto
RangeMut: ditto

src/liballoc/collections/btree/set.rs
Iter: Safe to call next_back, invokes no user defined code.
IntoIter: Not safe, changes Drop order
Range: Safe to call next_back, invokes no user defined code.

src/liballoc/collections/linked_list.rs
Iter: Safe to call next_back, invokes no user defined code.
IterMut: ditto
IntoIter: Not safe, changes Drop order

src/liballoc/collections/vec_deque.rs
Iter: Safe to call next_back, invokes no user defined code.
IterMut: ditto
IntoIter: Not safe, changes Drop order
Drain: ditto

src/liballoc/string.rs
Drain: Safe because return type is a primitive (char)

src/liballoc/vec.rs
IntoIter: Not safe, changes Drop order
Drain: ditto
Splice: ditto

src/libcore/ascii.rs
EscapeDefault: Safe because return type is a primitive (u8)

src/libcore/iter/adapters/chain.rs
Chain: Not safe, invokes user defined code (Iterator impl)

src/libcore/iter/adapters/flatten.rs
FlatMap: Not safe, invokes user defined code (Iterator impl)
Flatten: ditto
FlattenCompat: ditto

src/libcore/iter/adapters/mod.rs
Rev: Not safe, invokes user defined code (Iterator impl)
Copied: ditto
Cloned: Not safe, invokes user defined code (Iterator impl and T::clone)
Map: Not safe, invokes user defined code (Iterator impl + closure)
Filter: ditto
FilterMap: ditto
Enumerate: Not safe, invokes user defined code (Iterator impl)
Skip: ditto
Fuse: ditto
Inspect: ditto

src/libcore/iter/adapters/zip.rs
Zip: Not safe, invokes user defined code (Iterator impl)

src/libcore/iter/range.rs
ops::Range: Not safe, changes Drop order, but ALREADY HAS SPECIALIZATION
ops::RangeInclusive: ditto

src/libcore/iter/sources.rs
Repeat: Not safe, calling last should iloop.
Empty: No point, iterator is at most one item long.
Once: ditto
OnceWith: ditto

src/libcore/option.rs
Item: No point, iterator is at most one item long.
Iter: ditto
IterMut: ditto
IntoIter: ditto

src/libcore/result.rs
Iter: No point, iterator is at most one item long
IterMut: ditto
IntoIter: ditto

src/libcore/slice/mod.rs
Split: Not safe, invokes user defined closure
SplitMut: ditto
RSplit: ditto
RSplitMut: ditto
Windows: Safe, already has specialization
Chunks: ditto
ChunksMut: ditto
ChunksExact: ditto
ChunksExactMut: ditto
RChunks: ditto
RChunksMut: ditto
RChunksExact: ditto
RChunksExactMut: ditto

src/libcore/str/mod.rs
Chars: Safe, already has specialization
CharIndices: ditto
Bytes: ditto
Lines: Safe to call next_back, invokes no user defined code.
LinesAny: Deprecated
Everything that is generic over P: Pattern: Not safe because Pattern invokes user defined code.
SplitWhitespace: Safe to call next_back, invokes no user defined code.
SplitAsciiWhitespace: ditto

This is attempt 2 of rust-lang#60130.

r? @sfackler

… r=Centril

Migrate `compile-pass` annotations to `build-pass`

This is a part of rust-lang#62277.

As a first step, the `compile-pass` tests are migrated to `build-pass`.

r? @cramertj
cc @Centril

…t, r=alexcrichton

Fix bucket in CPU usage script

r? @alexcrichton

simplify Option::get_or_insert

I am pretty sure that the optimized result will be the same, and it's one `unsafe` less in the stdlib!

enable a few more tests in Miri and update the comment for others

remove bogus example from drop_in_place

Fixes rust-lang#62313