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+66
-11
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8 files changed

+66
-11
lines changed

‎compiler/rustc_parse/messages.ftl

+3
Original file line numberDiff line numberDiff line change
@@ -61,6 +61,9 @@ parse_bare_cr = {$double_quotes ->
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parse_bare_cr_in_raw_string = bare CR not allowed in raw string
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64+
parse_binder_before_modifiers = `for<...>` binder should be placed before trait bound modifiers
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.label = place the `for<...>` binder before any modifiers
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6467
parse_bounds_not_allowed_on_trait_aliases = bounds are not allowed on trait aliases
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parse_box_not_pat = expected pattern, found {$descr}

‎compiler/rustc_parse/src/errors.rs

+9
Original file line numberDiff line numberDiff line change
@@ -3028,3 +3028,12 @@ pub struct UnsafeAttrOutsideUnsafeSuggestion {
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#[suggestion_part(code = ")")]
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pub right: Span,
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}
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3032+
#[derive(Diagnostic)]
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#[diag(parse_binder_before_modifiers)]
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pub struct BinderBeforeModifiers {
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#[primary_span]
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pub binder_span: Span,
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#[label]
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pub modifiers_span: Span,
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}

‎compiler/rustc_parse/src/parser/ty.rs

+8
Original file line numberDiff line numberDiff line change
@@ -989,7 +989,10 @@ impl<'a> Parser<'a> {
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leading_token: &Token,
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) -> PResult<'a, GenericBound> {
991991
let (mut lifetime_defs, binder_span) = self.parse_late_bound_lifetime_defs()?;
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993+
let modifiers_lo = self.token.span;
992994
let modifiers = self.parse_trait_bound_modifiers()?;
995+
let modifiers_span = modifiers_lo.to(self.prev_token.span);
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994997
// Recover erroneous lifetime bound with modifiers or binder.
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// e.g. `T: for<'a> 'a` or `T: ~const 'a`.
@@ -998,6 +1001,11 @@ impl<'a> Parser<'a> {
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return self.parse_generic_lt_bound(lo, has_parens);
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}
10001003

1004+
if let (more_lifetime_defs, Some(binder_span)) = self.parse_late_bound_lifetime_defs()? {
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lifetime_defs.extend(more_lifetime_defs);
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self.dcx().emit_err(errors::BinderBeforeModifiers { binder_span, modifiers_span });
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}
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10011009
let mut path = if self.token.is_keyword(kw::Fn)
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&& self.look_ahead(1, |tok| tok.kind == TokenKind::OpenDelim(Delimiter::Parenthesis))
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&& let Some(path) = self.recover_path_from_fn()

‎src/tools/tidy/src/ui_tests.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -16,7 +16,7 @@ use std::path::{Path, PathBuf};
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const ENTRY_LIMIT: u32 = 900;
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// FIXME: The following limits should be reduced eventually.
1818

19-
const ISSUES_ENTRY_LIMIT: u32 = 1672;
19+
const ISSUES_ENTRY_LIMIT: u32 = 1673;
2020

2121
const EXPECTED_TEST_FILE_EXTENSIONS: &[&str] = &[
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"rs", // test source files

‎tests/ui/impl-trait/normalize-tait-in-const.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -24,7 +24,7 @@ mod foo {
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}
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use foo::*;
2626

27-
const fn with_positive<F: ~const for<'a> Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
27+
const fn with_positive<F: for<'a> ~const Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
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fun(filter_positive());
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}
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‎tests/ui/impl-trait/normalize-tait-in-const.stderr

+38-5
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,41 @@
1-
error: expected a trait, found type
2-
--> $DIR/normalize-tait-in-const.rs:27:34
1+
error: `~const` can only be applied to `#[const_trait]` traits
2+
--> $DIR/normalize-tait-in-const.rs:27:42
33
|
4-
LL | const fn with_positive<F: ~const for<'a> Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
5-
| ^^^^^^^^^^^^^^^^^^^^^^^^^
4+
LL | const fn with_positive<F: for<'a> ~const Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
5+
| ^^^^^^^^^^^^^^^^^
66

7-
error: aborting due to 1 previous error
7+
error: `~const` can only be applied to `#[const_trait]` traits
8+
--> $DIR/normalize-tait-in-const.rs:27:69
9+
|
10+
LL | const fn with_positive<F: for<'a> ~const Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
11+
| ^^^^^^^^
12+
13+
error[E0015]: cannot call non-const closure in constant functions
14+
--> $DIR/normalize-tait-in-const.rs:28:5
15+
|
16+
LL | fun(filter_positive());
17+
| ^^^^^^^^^^^^^^^^^^^^^^
18+
|
19+
= note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
20+
help: consider further restricting this bound
21+
|
22+
LL | const fn with_positive<F: for<'a> ~const Fn(&'a Alias<'a>) + ~const Destruct + ~const Fn(&foo::Alias<'_>)>(fun: F) {
23+
| ++++++++++++++++++++++++++++
24+
help: add `#![feature(effects)]` to the crate attributes to enable
25+
|
26+
LL + #![feature(effects)]
27+
|
28+
29+
error[E0493]: destructor of `F` cannot be evaluated at compile-time
30+
--> $DIR/normalize-tait-in-const.rs:27:79
31+
|
32+
LL | const fn with_positive<F: for<'a> ~const Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
33+
| ^^^ the destructor for this type cannot be evaluated in constant functions
34+
LL | fun(filter_positive());
35+
LL | }
36+
| - value is dropped here
37+
38+
error: aborting due to 4 previous errors
839

40+
Some errors have detailed explanations: E0015, E0493.
41+
For more information about an error, try `rustc --explain E0015`.

‎tests/ui/issues/issue-39089.rs

+1-1
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
11
fn f<T: ?for<'a> Sized>() {}
2-
//~^ ERROR expected a trait, found type
2+
//~^ ERROR `for<...>` binder should be placed before trait bound modifiers
33

44
fn main() {}

‎tests/ui/issues/issue-39089.stderr

+5-3
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,10 @@
1-
error: expected a trait, found type
2-
--> $DIR/issue-39089.rs:1:10
1+
error: `for<...>` binder should be placed before trait bound modifiers
2+
--> $DIR/issue-39089.rs:1:13
33
|
44
LL | fn f<T: ?for<'a> Sized>() {}
5-
| ^^^^^^^^^^^^^
5+
| - ^^^^
6+
| |
7+
| place the `for<...>` binder before any modifiers
68

79
error: aborting due to 1 previous error
810

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