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Don't refer to 'this tail expression' in expansion. - #142024

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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.

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@rustbotrustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Jun 4, 2025
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Comment threadtests/ui/never_type/feature-gate-never_type_fallback.stderr
Comment on lines -5 to -8
| --- ^^^^^^^^
| | |
| | the trait `T` is not implemented for `()`
| | this tail expression is of type `()`

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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"

The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.
-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes

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nit: s/hase/has in the commit message and PR description

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r=me after #142024 (comment) is addressed and CI is green.
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@m-ou-se
Don't refer to 'this tail expression' in expansion.
da2e33b
The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
@m-ou-se
m-ou-seforce-pushed the what-tail-expression branch from f19d2fe to da2e33bCompareJune 4, 2025 13:43
@m-ou-sem-ou-se mentioned this pull request Jun 4, 2025
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@bors r=petrochenkov rollup

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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
@bors
bors merged commit e081588 into rust-lang:masterJun 5, 2025
@rustbotrustbot added this to the 1.89.0 milestone Jun 5, 2025
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Unrolled build for#142024
96e60ab
Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
@m-ou-se
m-ou-se deleted the what-tail-expression branch June 5, 2025 08:08
christian-schilling pushed a commit to christian-schilling/rustc_codegen_cranelift that referenced this pull request Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
bd1ff92
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
christian-schilling pushed a commit to christian-schilling/rustc_codegen_cranelift that referenced this pull request Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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m-ou-se:what-tail-expression
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Don't refer to 'this tail expression' in expansion.#142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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Comment threadtests/ui/never_type/feature-gate-never_type_fallback.stderr

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 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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r=me after #142024 (comment) is addressed and CI is green.
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Don't refer to 'this tail expression' in expansion.
da2e33b
The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
@m-ou-se
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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
@bors
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merged commit e081588
into
rust-lang:masterJun 5, 2025
@rustbotrustbot
added this to the 1.89.0 milestone
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@rust-timer
Unrolled build for#142024
96e60ab
Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
@m-ou-se
m-ou-se
deleted the

what-tail-expression

branch
June 5, 2025 08:08
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
bd1ff92
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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rust-lang:masterfrom 
m-ou-se:what-tail-expression
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Don't refer to 'this tail expression' in expansion.#142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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Comment threadtests/ui/never_type/feature-gate-never_type_fallback.stderr

Comment on lines

-5
 to 
-8

 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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r=me after #142024 (comment) is addressed and CI is green.
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@m-ou-se
Don't refer to 'this tail expression' in expansion.
da2e33b
The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
@m-ou-se
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📌 Commit da2e33b has been approved by petrochenkov
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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
@bors
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merged commit e081588
into
rust-lang:masterJun 5, 2025
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added this to the 1.89.0 milestone
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@rust-timer
Unrolled build for#142024
96e60ab
Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
@m-ou-se
m-ou-se
deleted the

what-tail-expression

branch
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christian-schilling pushed a commit
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Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
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Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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Don't refer to 'this tail expression' in expansion.
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The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
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Unrolled build for#142024
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Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
@m-ou-se
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June 5, 2025 08:08
christian-schilling pushed a commit
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Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
bd1ff92
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
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Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
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var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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Don't refer to 'this tail expression' in expansion.#142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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Comment threadtests/ui/never_type/feature-gate-never_type_fallback.stderr

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 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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r=me after #142024 (comment) is addressed and CI is green.
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Don't refer to 'this tail expression' in expansion.
da2e33b
The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
@m-ou-se
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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
@bors
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merged commit e081588
into
rust-lang:masterJun 5, 2025
@rustbotrustbot
added this to the 1.89.0 milestone
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@rust-timer
Unrolled build for#142024
96e60ab
Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
@m-ou-se
m-ou-se
deleted the

what-tail-expression

branch
June 5, 2025 08:08
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
bd1ff92
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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Don't refer to 'this tail expression' in expansion.
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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
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Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
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Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
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Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
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Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
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Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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Don't refer to 'this tail expression' in expansion.#142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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Don't refer to 'this tail expression' in expansion.
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The user has no clue what tail expression the compiler is talking
about: it is an implementation detail of the macro that it uses a block
with tail expression.
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Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
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Unrolled build for#142024
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Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
@m-ou-se
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christian-schilling pushed a commit
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@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
bd1ff92
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
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`@rustbot` modify labels: rollup
christian-schilling pushed a commit
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@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
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Don't refer to 'this tail expression' in expansion. by m-ou-se · Pull Request #142024 · rust-lang/rust · GitHub
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Don't refer to 'this tail expression' in expansion. - #142024
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The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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 | --- ^^^^^^^^
 | | |
 | | the trait `T` is not implemented for `()`
 | | this tail expression is of type `()`
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"
The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.

-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes
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nit: s/hase/has in the commit message and PR description
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Don't refer to 'this tail expression' in expansion.
da2e33b
The user has no clue what tail expression the compiler is talking
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with tail expression.
@m-ou-se
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@bors r=petrochenkov rollup
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📌 Commit da2e33b has been approved by petrochenkov
It is now in the queue for this repository.
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@bors
Auto merge of#142033- matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
81a964c
Rollup of 11 pull requests
Successful merges:
- #141890 (Add link to correct documentation in htmldocck.py)
- #141932 (Fix for async drop inside async gen fn)
- #141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- #141968 (Run wfcheck in one big loop instead of per module)
- #141969 (Triagebot: Remove `assign.users_on_vacation`)
- #141985 (Ensure query keys are printed with reduced queries)
- #141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- #142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- #142017 (Fix incorrect use of "recommend" over "recommended")
- #142024 (Don't refer to 'this tail expression' in expansion.)
- #142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
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rust-lang:masterJun 5, 2025
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Unrolled build for#142024
96e60ab
Rollup merge of #142024 - m-ou-se:what-tail-expression, r=petrochenkov
Don't refer to 'this tail expression' in expansion.
The user has no clue what the compiler is talking about when it says "this tail expression". It is an implementation detail of the macro that it uses a block with tail expression.
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June 5, 2025 08:08
christian-schilling pushed a commit
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Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
bd1ff92
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
christian-schilling pushed a commit
to christian-schilling/rustc_codegen_cranelift
that referenced
this pull request
Jan 27, 2026
@bors
Auto merge of #142033 - matthiaskrgr:rollup-99lvg0j, r=matthiaskrgr
99c29ec
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#141890 (Add link to correct documentation in htmldocck.py)
- rust-lang/rust#141932 (Fix for async drop inside async gen fn)
- rust-lang/rust#141960 (Use non-2015 edition paths in tests that do not test for their resolution)
- rust-lang/rust#141968 (Run wfcheck in one big loop instead of per module)
- rust-lang/rust#141969 (Triagebot: Remove `assign.users_on_vacation`)
- rust-lang/rust#141985 (Ensure query keys are printed with reduced queries)
- rust-lang/rust#141999 (Visit the ident in `PreciseCapturingNonLifetimeArg`.)
- rust-lang/rust#142005 (Change `tag_field` to `FieldIdx` in `Variants::Multiple`)
- rust-lang/rust#142017 (Fix incorrect use of "recommend" over "recommended")
- rust-lang/rust#142024 (Don't refer to 'this tail expression' in expansion.)
- rust-lang/rust#142025 (Don't refer to 'local binding' in extern macro.)
r? `@ghost`
`@rustbot` modify labels: rollup
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