Merging upstream version 1.74.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 21 insertions, 10 deletions

diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index a2729b374..8b15e8269 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -20,11 +20,19 @@
 // FIXME: Fill me in with more detail when the interface settles
 //! This library is built on the assumption of a few existing symbols:
 //!
-//! * `memcpy`, `memcmp`, `memset`, `strlen` - These are core memory routines which are
-//!   often generated by LLVM. Additionally, this library can make explicit
-//!   calls to these functions. Their signatures are the same as found in C.
-//!   These functions are often provided by the system libc, but can also be
-//!   provided by the [compiler-builtins crate](https://crates.io/crates/compiler_builtins).
+//! * `memcpy`, `memmove`, `memset`, `memcmp`, `bcmp`, `strlen` - These are core memory routines
+//!   which are generated by Rust codegen backends. Additionally, this library can make explicit
+//!   calls to `strlen`. Their signatures are the same as found in C, but there are extra
+//!   assumptions about their semantics: For `memcpy`, `memmove`, `memset`, `memcmp`, and `bcmp`, if
+//!   the `n` parameter is 0, the function is assumed to not be UB. Furthermore, for `memcpy`, if
+//!   source and target pointer are equal, the function is assumed to not be UB.
+//!   (Note that these are [standard assumptions](https://reviews.llvm.org/D86993) among compilers.)
+//!   These functions are often provided by the system libc, but can also be provided by the
+//!   [compiler-builtins crate](https://crates.io/crates/compiler_builtins).
+//!   Note that the library does not guarantee that it will always make these assumptions, so Rust
+//!   user code directly calling the C functions should follow the C specification! The advice for
+//!   Rust user code is to call the functions provided by this library instead (such as
+//!   `ptr::copy`).
 //!
 //! * `rust_begin_panic` - This function takes four arguments, a
 //!   `fmt::Arguments`, a `&'static str`, and two `u32`'s. These four arguments
@@ -96,12 +104,14 @@
 #![allow(explicit_outlives_requirements)]
 #![allow(incomplete_features)]
 #![warn(multiple_supertrait_upcastable)]
-#![cfg_attr(not(bootstrap), allow(internal_features))]
+#![allow(internal_features)]
 // Do not check link redundancy on bootstraping phase
-#![cfg_attr(not(bootstrap), allow(rustdoc::redundant_explicit_links))]
+#![allow(rustdoc::redundant_explicit_links)]
 //
 // Library features:
 // tidy-alphabetical-start
+#![cfg_attr(bootstrap, feature(no_coverage))] // rust-lang/rust#84605
+#![cfg_attr(not(bootstrap), feature(coverage_attribute))] // rust-lang/rust#84605
 #![feature(char_indices_offset)]
 #![feature(const_align_of_val)]
 #![feature(const_align_of_val_raw)]
@@ -152,12 +162,10 @@
 #![feature(const_slice_from_raw_parts_mut)]
 #![feature(const_slice_from_ref)]
 #![feature(const_slice_index)]
-#![feature(const_slice_is_ascii)]
 #![feature(const_slice_ptr_len)]
 #![feature(const_slice_split_at_mut)]
 #![feature(const_str_from_utf8_unchecked_mut)]
 #![feature(const_swap)]
-#![feature(const_transmute_copy)]
 #![feature(const_try)]
 #![feature(const_type_id)]
 #![feature(const_type_name)]
@@ -170,6 +178,7 @@
 #![feature(ip)]
 #![feature(ip_bits)]
 #![feature(is_ascii_octdigit)]
+#![feature(isqrt)]
 #![feature(maybe_uninit_uninit_array)]
 #![feature(ptr_alignment_type)]
 #![feature(ptr_metadata)]
@@ -228,7 +237,6 @@
 #![feature(negative_impls)]
 #![feature(never_type)]
 #![feature(no_core)]
-#![feature(no_coverage)] // rust-lang/rust#84605
 #![feature(platform_intrinsics)]
 #![feature(prelude_import)]
 #![feature(repr_simd)]
@@ -282,6 +290,9 @@ pub mod assert_matches {
     pub use crate::macros::{assert_matches, debug_assert_matches};
 }
 
+#[unstable(feature = "cfg_match", issue = "115585")]
+pub use crate::macros::cfg_match;
+
 #[macro_use]
 mod internal_macros;