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Unrolled build for rust-lang#139668
Rollup merge of rust-lang#139668 - matthewjasper:upper-bound-fix, r=compiler-errors Handle regions equivalent to 'static in non_local_bounds `non_local_bounds` would only find non local bounds that strictly bound a given region, but it's possible that a local region is equated to 'static when showing a type referencing a locally bound lifetime, such as `dyn Any + 'a` in the tests added, is well-formed. In this case we should return 'static. closes rust-lang#122704 closes rust-lang#139004
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lines changed

‎compiler/rustc_borrowck/src/type_check/free_region_relations.rs‎

Lines changed: 2 additions & 1 deletion
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@@ -131,7 +131,8 @@ impl UniversalRegionRelations<'_> {
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assert!(self.universal_regions.is_universal_region(fr0));
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let mut external_parents = vec![];
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let mut queue = vec![fr0];
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let mut queue = vec![relation.minimal_scc_representative(fr0)];
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// Keep expanding `fr` into its parents until we reach
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// non-local regions.

‎compiler/rustc_data_structures/src/transitive_relation.rs‎

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@@ -354,6 +354,20 @@ impl<T: Eq + Hash + Copy> TransitiveRelation<T> {
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.collect()
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}
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/// Given an element A, elements B with the lowest index such that `A R B`
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/// and `B R A`, or `A` if no such element exists.
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pub fn minimal_scc_representative(&self, a: T) -> T {
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match self.index(a) {
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Some(a_i) => self.with_closure(|closure| {
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closure
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.iter(a_i.0)
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.find(|i| closure.contains(*i, a_i.0))
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.map_or(a, |i| self.elements[i])
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}),
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None => a,
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}
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}
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fn with_closure<OP, R>(&self, op: OP) -> R
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where
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OP: FnOnce(&BitMatrix<usize, usize>) -> R,

‎compiler/rustc_data_structures/src/transitive_relation/tests.rs‎

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@@ -376,3 +376,44 @@ fn parent() {
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let p = relation.postdom_parent(3);
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assert_eq!(p, Some(0));
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}
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#[test]
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fn minimal_scc_representative_1() {
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// +---------+
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// v |
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// a -> c -> d -> e
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// ^ ^
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// | |
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// b ---+
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// "digraph { a -> c -> d -> e -> c; b -> d; b -> e; }",
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let mut relation = TransitiveRelationBuilder::default();
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relation.add("a", "c");
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relation.add("c", "d");
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relation.add("d", "e");
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relation.add("e", "c");
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relation.add("b", "d");
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relation.add("b", "e");
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let relation = relation.freeze();
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assert_eq!(relation.minimal_scc_representative("a"), "a");
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assert_eq!(relation.minimal_scc_representative("b"), "b");
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assert_eq!(relation.minimal_scc_representative("c"), "c");
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assert_eq!(relation.minimal_scc_representative("d"), "c");
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assert_eq!(relation.minimal_scc_representative("e"), "c");
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}
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#[test]
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fn minimal_scc_representative_2() {
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// "digraph { a -> b; a -> a; b -> a; c -> c}",
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let mut relation = TransitiveRelationBuilder::default();
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relation.add("a", "b");
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relation.add("b", "a");
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relation.add("a", "a");
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relation.add("c", "c");
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let relation = relation.freeze();
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assert_eq!(relation.minimal_scc_representative("a"), "a");
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assert_eq!(relation.minimal_scc_representative("b"), "a");
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assert_eq!(relation.minimal_scc_representative("c"), "c");
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}

‎tests/crashes/122704.rs‎

Lines changed: 0 additions & 14 deletions
This file was deleted.

‎tests/ui/borrowck/unconstrained-closure-lifetime-generic.rs‎

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@@ -0,0 +1,22 @@
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// Regression test for #122704
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use std::any::Any;
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pub struct Foo {
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bar: Box<dyn for<'a> Fn(&'a usize) -> Box<dyn Any + 'a>>,
6+
}
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impl Foo {
9+
pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I>) {
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self.bar = Box::new(|baz| Box::new(f(baz)));
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//~^ ERROR the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
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//~| ERROR the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
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//~| ERROR the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
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//~| ERROR the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
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//~| ERROR the parameter type `I` may not live long enough
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//~| ERROR the parameter type `I` may not live long enough
17+
//~| ERROR the parameter type `I` may not live long enough
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//~| ERROR `f` does not live long enough
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}
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}
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fn main() {}

‎tests/ui/borrowck/unconstrained-closure-lifetime-generic.stderr‎

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1+
error[E0310]: the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
2+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:9
3+
|
4+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
5+
| ^^^^^^^^
6+
| |
7+
| the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` must be valid for the static lifetime...
8+
| ...so that the type `impl for<'a> Fn(&'a usize) -> Box<I>` will meet its required lifetime bounds
9+
|
10+
help: consider adding an explicit lifetime bound
11+
|
12+
LL | pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I> + 'static) {
13+
| +++++++++
14+
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error[E0310]: the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
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--> $DIR/unconstrained-closure-lifetime-generic.rs:10:9
17+
|
18+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
19+
| ^^^^^^^^
20+
| |
21+
| the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` must be valid for the static lifetime...
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| ...so that the type `impl for<'a> Fn(&'a usize) -> Box<I>` will meet its required lifetime bounds
23+
|
24+
= note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
25+
help: consider adding an explicit lifetime bound
26+
|
27+
LL | pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I> + 'static) {
28+
| +++++++++
29+
30+
error[E0310]: the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
31+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:20
32+
|
33+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
34+
| ^^^^^^^^
35+
| |
36+
| the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` must be valid for the static lifetime...
37+
| ...so that the type `impl for<'a> Fn(&'a usize) -> Box<I>` will meet its required lifetime bounds
38+
|
39+
help: consider adding an explicit lifetime bound
40+
|
41+
LL | pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I> + 'static) {
42+
| +++++++++
43+
44+
error[E0310]: the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` may not live long enough
45+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:20
46+
|
47+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
48+
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
49+
| |
50+
| the parameter type `impl for<'a> Fn(&'a usize) -> Box<I>` must be valid for the static lifetime...
51+
| ...so that the type `impl for<'a> Fn(&'a usize) -> Box<I>` will meet its required lifetime bounds
52+
|
53+
help: consider adding an explicit lifetime bound
54+
|
55+
LL | pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I> + 'static) {
56+
| +++++++++
57+
58+
error[E0310]: the parameter type `I` may not live long enough
59+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:35
60+
|
61+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
62+
| ^^^^^^^^^^^^^^^^
63+
| |
64+
| the parameter type `I` must be valid for the static lifetime...
65+
| ...so that the type `I` will meet its required lifetime bounds
66+
|
67+
help: consider adding an explicit lifetime bound
68+
|
69+
LL | pub fn ack<I: 'static>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I>) {
70+
| +++++++++
71+
72+
error[E0310]: the parameter type `I` may not live long enough
73+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:35
74+
|
75+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
76+
| ^^^^^^^^^^^^^^^^
77+
| |
78+
| the parameter type `I` must be valid for the static lifetime...
79+
| ...so that the type `I` will meet its required lifetime bounds
80+
|
81+
= note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
82+
help: consider adding an explicit lifetime bound
83+
|
84+
LL | pub fn ack<I: 'static>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I>) {
85+
| +++++++++
86+
87+
error[E0311]: the parameter type `I` may not live long enough
88+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:35
89+
|
90+
LL | pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I>) {
91+
| --------- the parameter type `I` must be valid for the anonymous lifetime defined here...
92+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
93+
| ^^^^^^^^^^^^^^^^ ...so that the type `I` will meet its required lifetime bounds
94+
|
95+
help: consider adding an explicit lifetime bound
96+
|
97+
LL | pub fn ack<'a, I: 'a>(&'a mut self, f: impl for<'a> Fn(&'a usize) -> Box<I>) {
98+
| +++ ++++ ++
99+
100+
error[E0597]: `f` does not live long enough
101+
--> $DIR/unconstrained-closure-lifetime-generic.rs:10:44
102+
|
103+
LL | pub fn ack<I>(&mut self, f: impl for<'a> Fn(&'a usize) -> Box<I>) {
104+
| - binding `f` declared here
105+
LL | self.bar = Box::new(|baz| Box::new(f(baz)));
106+
| -------- ----- ^ borrowed value does not live long enough
107+
| | |
108+
| | value captured here
109+
| coercion requires that `f` is borrowed for `'static`
110+
...
111+
LL | }
112+
| - `f` dropped here while still borrowed
113+
|
114+
= note: due to object lifetime defaults, `Box<dyn for<'a> Fn(&'a usize) -> Box<(dyn Any + 'a)>>` actually means `Box<(dyn for<'a> Fn(&'a usize) -> Box<(dyn Any + 'a)> + 'static)>`
115+
116+
error: aborting due to 8 previous errors
117+
118+
Some errors have detailed explanations: E0310, E0311, E0597.
119+
For more information about an error, try `rustc --explain E0310`.

‎tests/ui/borrowck/unconstrained-closure-lifetime-trait-object.rs‎

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@@ -0,0 +1,11 @@
1+
// Regression test for #139004
2+
use std::any::Any;
3+
4+
type B = Box<dyn for<'a> Fn(&(dyn Any + 'a)) -> Box<dyn Any + 'a>>;
5+
6+
fn foo<E>() -> B {
7+
Box::new(|e| Box::new(e.is::<E>()))
8+
//~^ ERROR the parameter type `E` may not live long enough
9+
}
10+
11+
fn main() {}

‎tests/ui/borrowck/unconstrained-closure-lifetime-trait-object.stderr‎

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1+
error[E0310]: the parameter type `E` may not live long enough
2+
--> $DIR/unconstrained-closure-lifetime-trait-object.rs:7:29
3+
|
4+
LL | Box::new(|e| Box::new(e.is::<E>()))
5+
| ^^
6+
| |
7+
| the parameter type `E` must be valid for the static lifetime...
8+
| ...so that the type `E` will meet its required lifetime bounds
9+
|
10+
help: consider adding an explicit lifetime bound
11+
|
12+
LL | fn foo<E: 'static>() -> B {
13+
| +++++++++
14+
15+
error: aborting due to 1 previous error
16+
17+
For more information about this error, try `rustc --explain E0310`.

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