Merge #536

536: Update to 1.82 and 1.83 r=tshepang a=Veykril

Builds atop of #529 

Co-authored-by: Lukas Wirth <[email protected]>

src/attributes.rst

@@ -157,6 +157,7 @@ Built-in Attributes
      | TestContent
      | TrackCallerContent
      | TypeLengthLimitContent
+     | UnsafeContent
      | UsedContent
      | WindowsSubsystemContent
 
@@ -226,6 +227,9 @@ The following :t:`[built-in attribute]s` are :dt:`[diagnostics attribute]s`:
 * :dp:`fls_NrTL2FruARAv`
   :t:`Attribute` ``expect``.
 
+* :dp:`fls_4d2ArC50kNWL`
+  :t:`Attribute` ``unsafe``.
+
 :dp:`fls_3fxhz0olhbcy`
 The following :t:`[built-in attribute]s` are :dt:`[documentation attribute]s`:
 
@@ -1358,6 +1362,45 @@ related :t:`type`.
        second_field: i8
    }
 
+.. _fls_19LnTi3WabFd:
+
+Attribute ``unsafe``
+^^^^^^^^^^^^^^^^^^^^
+
+.. rubric:: Syntax
+
+.. syntax::
+
+   UnsafeContent ::=
+       $$unsafe$$ $$($$ BuiltinAttributeContent $$)$$
+
+.. rubric:: Legality Rules
+
+:dp:`fls_5pjo3nGOxbVw`
+:t:`Attribute` :c:`unsafe` shall apply to what the contained :t:`attribute` applies to.
+
+:dp:`fls_gpxlWbQUNsj8`
+:t:`Attribute` :c:`unsafe` behaves like the contained :t:`attribute`.
+
+:dp:`fls_PhrfxSBvXTPV`
+The contained :t:`attribute` shall be one of:
+
+* :dp:`fls_pCSew95bKJJ5`
+  :t:`attribute` :c:`no_mangle`,
+
+  :dp:`fls_NRLgmOXxuljQ`
+  :t:`attribute` :c:`export_name`, or
+
+  :dp:`fls_ykpxNByUDyHG`
+  :t:`attribute` :c:`link_section`,
+
+.. rubric:: Examples
+
+.. code-block:: rust
+
+   #[unsafe(no_mangle)]
+   pub fn clear_name() {}
+
 .. _fls_7skf24auayqy:
 
 Attribute ``used``

src/changelog.rst

@@ -18,6 +18,134 @@ with the change that has been applied due to it.
    just the language changes that had an impact to the FLS. See the `release
    notes`_ for a full list of changes.
 
+Language changes in Rust 1.83.0
+-------------------------------
+
+* `Stabilize \`&mut\`, \`*mut\`, \`&Cell\`, and \`*const Cell\` in const. <https://github.com/rust-lang/rust/pull/129195>`_
+
+  * Changed paragraphs: :p:`fls_to4e7imq2c0w`, :p:`fls_6g7c1kjrmfnr`, :p:`fls_hkbwa8xx2fwx`
+
+* `Allow creating references to statics in \`const\` initializers. <https://github.com/rust-lang/rust/pull/129759>`_
+
+  * No change: This previous restriction is not specified in the FLS
+
+* `Implement raw lifetimes and labels (\`'r#ident\`). <https://github.com/rust-lang/rust/pull/126452>`_
+
+  * Changed syntax: :s:`Lifetime`
+
+* `Define behavior when atomic and non-atomic reads race. <https://github.com/rust-lang/rust/pull/128778>`_
+
+  * No change: Already covered by the definition of :t:`data race`.
+
+* `Non-exhaustive structs may now be empty. <https://github.com/rust-lang/rust/pull/128934>`_
+
+  * Removed paragraph: :p:`fls_2CWUWbYT9KcT`
+
+  * Changed paragraph: :p:`fls_fSNrRsgzLd0E`, :p:`fls_S9QL6yVF5LFI`
+
+* `Disallow implicit coercions from places of type \`!\` <https://github.com/rust-lang/rust/pull/129392>`_
+
+  * No change: The FLS does not specify type inference to such a degree
+
+* `\`const extern\` functions can now be defined for other calling conventions. <https://github.com/rust-lang/rust/pull/129753>`_
+
+  * No change: This previous restriction is not specified in the FLS
+
+* `Stabilize \`expr_2021\` macro fragment specifier in all editions. <https://github.com/rust-lang/rust/pull/129972>`_
+
+  * Changed syntax: :s:`MacroFragmentSpecifier`
+
+  * Changed paragraphs: :p:`fls_k00bck2k8tde`, :p:`fls_PxR9vNHsaFnI`
+
+* `The \`non_local_definitions\` lint now fires on less code and warns by default. <https://github.com/rust-lang/rust/pull/127117>`_
+
+  * No change: Lints are not part of the FLS
+
+Language changes in Rust 1.82.0
+-------------------------------
+
+* `Don't make statement nonterminals match pattern nonterminals <https://github.com/rust-lang/rust/pull/120221/>`_
+
+  * No change: Exact parsing behavior of non-terminals within declarative macros is not specified
+
+* `Patterns matching empty types can now be omitted in common cases <https://github.com/rust-lang/rust/pull/122792>`_
+
+  * New section: :ref:`fls_mcxF9y5u66sZ`
+
+  * Changed paragraphs: :p:`fls_9fjspnefoyvz`, :p:`fls_uq7ftuuq1sig`, :p:`fls_cfoy86mkmqa4`, :p:`fls_rnppz6y5z8pi`, :p:`fls_x0bmzl1315gq`, :p:`fls_MK83WE0iDqNf`
+
+* `Enforce supertrait outlives obligations when using trait impls <https://github.com/rust-lang/rust/pull/124336>`_
+
+  * No change: the concrete type inference resolution is not part of the FLS
+
+* `\`addr_of(_mut)!\` macros and the newly stabilized \`&raw (const|mut)\` are now safe to use with all static items <https://github.com/rust-lang/rust/pull/125834>`_
+
+  * No change: `addr_of` is not specified as it is a library defined macro, `&raw (const|mut)` appears as a new feature separately below
+
+* `size_of_val_raw: for length 0 this is safe to call <https://github.com/rust-lang/rust/pull/126152/>`_
+
+  * No change: `size_of_val_raw` is a library defined function
+
+* `Reorder trait bound modifiers *after* \`for<...>\` binder in trait bounds <https://github.com/rust-lang/rust/pull/127054/>`_
+
+  * Changed syntax: :s:`TraitBound`
+
+* `Stabilize opaque type precise capturing (RFC 3617) <https://github.com/rust-lang/rust/pull/127672>`_
+
+  * Changed syntax: :s:`ImplTraitTypeSpecification`, :s:`ImplTraitTypeSpecificationOneBound`
+
+  * New syntax: :s:`UseCaptures`, :s:`UseCapturesGenericArgs`, :s:`UseCapturesGenericArg`
+
+  * New paragraphs: :p:`fls_69hqMjvNno9u`, :p:`fls_OnyR0Wsfk7KI`, :p:`fls_KgH6c5cC4S0G`, :p:`fls_iT9WCNfUZQnC`
+
+* `Stabilize \`&raw const\` and \`&raw mut\` operators (RFC 2582) <https://github.com/rust-lang/rust/pull/127679>`_
+
+  * New section: :ref:`fls_vXGuvRWOLbEE`
+
+  * New paragraphs: :p:`fls_K7SbApHPmwjM`
+
+* `Stabilize unsafe extern blocks (RFC 3484) <https://github.com/rust-lang/rust/pull/127921>`_
+
+  * New syntax: :s:`ItemSafety`
+
+  * Changed syntax: :s:`WeakKeyword`, :s:`FunctionQualifierList`, :s:`StaticDeclaration`
+
+  * New paragraphs: :p:`fls_8ltVLtAfvy0m`, :p:`fls_WRpcVF1fLEpr`, :p:`fls_8ltVLtAfvy0m`
+
+  * Changed paragraphs: :p:`fls_g0JEluWqBpNc`, :p:`fls_7ucwmzqtittv`, :p:`fls_4dje9t5y2dia`, :p:`fls_l88r9fj82650`, :p:`fls_fo9with6xumo`
+
+  * Removed paragraph :p:`fls_iaimuqcclstl`
+
+* `Stabilize nested field access in \`offset_of!\` <https://github.com/rust-lang/rust/pull/128284>`_
+
+  * No change: `offset_of` is a library defined macro
+
+* `Do not require \`T\` to be live when dropping \`[T; 0]\` <https://github.com/rust-lang/rust/pull/128438>`_
+
+  * No change: The drop interaction with the borrow checker is not specified as the borrow checker is not specified in the FLS
+
+* `Stabilize \`const\` operands in inline assembly <https://github.com/rust-lang/rust/pull/128570>`_
+
+  * Note: These changes affect content that is informational.
+
+  * New syntax: :s:`ConstRegisterExpression`
+
+  * New paragraphs: :p:`fls_81Ju1TEqJ48K`, :p:`fls_j9XOoXDmN5Dq`, :p:`fls_jU8zg4k8dFsY`
+
+* `Stabilize floating-point arithmetic in \`const fn\` <https://github.com/rust-lang/rust/pull/128596>`_
+
+  * New paragraph: :p:`fls_lSxXWxJn0vMO`
+
+  * Removed paragraph: :p:`fls_9mrrosm8jnn7`
+
+* `Stabilize explicit opt-in to unsafe attributes <https://github.com/rust-lang/rust/pull/128771>`_
+
+  * New section: :ref:`fls_19LnTi3WabFd`
+
+* `Document NaN bit patterns guarantees <https://github.com/rust-lang/rust/pull/129559>`_
+
+  * New paragraph: :p:`fls_nuFAwLHOdQBx`
+
 Language changes in Rust 1.81.0
 -------------------------------
 

src/expressions.rst

@@ -194,8 +194,7 @@ involve :t:`[type]s` that require :t:`destruction`:
   :t:`[Constant parameter]s`,
 
 * :dp:`fls_to4e7imq2c0w`
-  :t:`[Dereference expression]s` when the :t:`operand` is not of a
-  :t:`raw pointer type`,
+  :t:`[Dereference expression]s`,
 
 * :dp:`fls_krtbrpwf3mh0`
   :t:`[Expression statement]s`,
@@ -211,8 +210,7 @@ involve :t:`[type]s` that require :t:`destruction`:
   :t:`[If let expression]s`,
 
 * :dp:`fls_6g7c1kjrmfnr`
-  :t:`[Immutable borrow expression]s` where the borrowed :t:`type` is not
-  subject to :t:`interior mutability`.
+  :t:`[Immutable borrow expression]s`.
 
 * :dp:`fls_rpapnm3afan8`
   :t:`[Index expression]s`,
@@ -251,8 +249,7 @@ involve :t:`[type]s` that require :t:`destruction`:
   :t:`[Range expression]s`,
 
 * :dp:`fls_hkbwa8xx2fwx`
-  :t:`[Shared borrow]s` that do not involve :t:`[type]s` with
-  :t:`interior mutability`,
+  :t:`[Borrow]s`,
 
 * :dp:`fls_fobs8ebt7dhc`
   :t:`[Struct expression]s`,
@@ -280,11 +277,6 @@ explicitly invokes an :t:`associated trait function` or uses
 :t:`[arithmetic operator]s` of non-builtin :t:`[type]s` that invoke
 :std:`core::ops` :t:`[trait]s`.
 
-:dp:`fls_9mrrosm8jnn7`
-An :t:`arithmetic expression` that operates with :t:`[floating-point value]s` is
-not considered a :t:`constant expression` when it appears inside the
-:t:`function body` of a :t:`constant function`.
-
 :dp:`fls_fmqar6o1bwqk`
 It is a static error if the :t:`size operand` of an
 :t:`array repetition constructor` or an :t:`array type` depends on
@@ -482,6 +474,9 @@ The following :t:`[construct]s` are :t:`[place expression context]s`:
 * :dp:`fls_Ufz9W5vyZkv3`
   The :t:`operand` of a :t:`borrow expression`,
 
+* :dp:`fls_K7SbApHPmwjM`
+  The :t:`operand` of a :t:`raw borrow expression`,
+
 * :dp:`fls_KxWIzoh9WwK7`
   The :t:`operand` of a :t:`dereference expression`,
 
@@ -927,13 +922,19 @@ Operator Expressions
      | ErrorPropagationExpression
      | LazyBooleanExpression
      | NegationExpression
+     | RawBorrowExpression
      | TypeCastExpression
 
 .. rubric:: Legality Rules
 
 :dp:`fls_ursc5ynymoy`
 An :t:`operator expression` is an :t:`expression` that involves an operator.
 
+.. rubric:: Dynamic Semantics
+
+:dp:`fls_lSxXWxJn0vMO`
+An :t:`operator expression` that operates with :t:`[floating-point value]s` run as a :t:`constant expression` is allowed to yield different :t:`[value]s` compared to when run as a non-:t:`constant expression`.
+
 .. _fls_qztk0bkju9u:
 
 Borrow Expression
@@ -971,11 +972,11 @@ state, or simply :t:`borrowed`.
 The :t:`type` of a :t:`borrow expression` is determined as follows:
 
 * :dp:`fls_5b2x5ri2w54r`
-  If the :t:`borrow expression` denotes a :t:`shared reference`, then the
+  If the :t:`borrow expression` denotes an :t:`immutable borrow expression`, then the
   :t:`type` is ``&T``, where ``T`` is the :t:`type` of the :t:`operand`.
 
 * :dp:`fls_agl09ia869rk`
-  If the :t:`borrow expression` denotes a :t:`mutable reference`, then the
+  If the :t:`borrow expression` denotes a :t:`mutable borrow expression`, then the
   :t:`type` is ``&mut T``, where ``T`` is the :t:`type` of the :t:`operand`.
 
 :dp:`fls_8cvmee9bzs40`
@@ -2057,6 +2058,65 @@ The :t:`evaluation` of a :t:`lazy or expression` proceeds as follows:
    false && panic!()
    this || that
 
+.. _fls_vXGuvRWOLbEE:
+
+Raw Borrow Expression
+~~~~~~~~~~~~~~~~~~~~~
+
+.. rubric:: Syntax
+
+.. syntax::
+
+   RawBorrowExpression ::=
+       $$&$$ $$raw$$ ($$const$$ | $$mut$$) Operand
+
+.. rubric:: Legality Rules
+
+:dp:`fls_TS6DvMon5h27`
+A :t:`raw borrow expression` is an :t:`expression` that creates a :t:`raw pointer` to the memory location of its :t:`operand` without incurring a :t:`borrow`.
+
+:dp:`fls_UtjWrE2qeplQ`
+An :dt:`immutable raw borrow expression` is a :t:`raw borrow expression` that has :t:`keyword` ``const``.
+
+:dp:`fls_4e7EE4a8Yvmy`
+A :dt:`mutable raw borrow expression` is a :t:`raw borrow expression` that has :t:`keyword` ``mut``.
+
+:dp:`fls_gOXUWePymgGV`
+When the :t:`operand` of a :t:`raw borrow expression` is a :t:`place expression`, the :t:`raw borrow expression` produces a :t:`raw pointer` to the memory location indicated by the :t:`operand`.
+
+:dp:`fls_YBC8GrIBzZbi`
+It is a static error if the :t:`operand` of a :t:`raw borrow expression` is a :t:`temporary`.
+
+:dp:`fls_Twkre8IzUa8S`
+The :t:`type` of a :t:`raw borrow expression` is determined as follows:
+
+* :dp:`fls_Ki4FOzJMqtvJ`
+  If the :t:`raw borrow expression` denotes an :t:`immutable raw borrow expression`, then the :t:`type` is ``*const T``, where ``T`` is the :t:`type` of the :t:`operand`.
+
+* :dp:`fls_DJxQDBsO9hc7`
+  If the :t:`raw borrow expression` denotes a :t:`mutable raw borrow expression`, then the :t:`type` is ``*mut T``, where ``T`` is the :t:`type` of the :t:`operand`.
+
+:dp:`fls_WlXB0AHifCdd`
+The :t:`value` of a :t:`raw borrow expression` is the address of its :t:`operand`.
+
+.. rubric:: Dynamic Semantics
+
+:dp:`fls_qQrV8QuGGcVO`
+The :t:`evaluation` of a :t:`raw borrow expression` evaluates its :t:`operand`.
+
+.. rubric:: Examples
+
+.. code-block:: rust
+
+   let mut answer = 42;
+
+:dp:`fls_dTABiwAPGhdZ`
+Mutable raw borrow.
+
+.. syntax::
+
+   let ref_answer = &raw mut answer;
+
 .. _fls_1qhsun1vyarz:
 
 Type Cast Expressions

src/ffi.rst

@@ -160,7 +160,10 @@ External Blocks
 
 :dp:`fls_4dje9t5y2dia`
 An :t:`external block` is a :t:`construct` that provides the declarations of
-foreign :t:`[function]s` as unchecked imports.
+:t:`[external function]s` and :t:`[external static]s` as unchecked imports.
+
+:dp:`fls_8ltVLtAfvy0m`
+An :t:`unsafe external block` is an :t:`external block` subject to keyword ``unsafe``.
 
 :dp:`fls_Nz0l16hMxqTd`
 The :t:`ABI` of an :t:`external block` is determined as follows:
@@ -171,10 +174,6 @@ The :t:`ABI` of an :t:`external block` is determined as follows:
 * :dp:`fls_PBsepNHImJKH`
   Otherwise the :t:`ABI` is the :t:`extern C ABI`.
 
-:dp:`fls_iaimuqcclstl`
-The ``unsafe`` :t:`keyword` of an :t:`external block` is rejected, but may
-still be consumed by :t:`[macro]s`.
-
 .. rubric:: Examples
 
 .. code-block:: rust
@@ -201,7 +200,7 @@ External Functions
 An :t:`external function` is an unchecked import of a foreign :t:`function`.
 
 :dp:`fls_l88r9fj82650`
-An :t:`external function` shall be invoked from an :t:`unsafe context`.
+An :t:`external function` shall be invoked from an :t:`unsafe context` unless it is defined in an :t:`unsafe external block` and subject to :s:`ItemSafety` with keyword ``safe``.
 
 :dp:`fls_qwchgvvnp0qe`
 An :t:`external function` shall not specify a :s:`FunctionQualifierList`.
@@ -240,7 +239,7 @@ An :t:`external static` inherits the :t:`ABI` of its enclosing
 :t:`external block`.
 
 :dp:`fls_fo9with6xumo`
-An :t:`external static` shall be referenced from an :t:`unsafe context`.
+An :t:`external static` shall be referenced from an :t:`unsafe context` unless it is defined in an :t:`unsafe external block` and subject to :s:`ItemSafety` with keyword ``safe``.
 
 :dp:`fls_tr7purzcldn0`
 An :t:`external static` shall not specify a :t:`static initializer`.