Point at lifetime requirement origin in more cases

21 files changed, 93 insertions, 51 deletions

diff --git a/compiler/rustc_borrowck/src/borrowck_errors.rs b/compiler/rustc_borrowck/src/borrowck_errors.rs
index bc985cbe133..7c9011505d6 100644
--- a/compiler/rustc_borrowck/src/borrowck_errors.rs
+++ b/compiler/rustc_borrowck/src/borrowck_errors.rs
@@ -480,7 +480,7 @@ impl<'infcx, 'tcx> crate::MirBorrowckCtxt<'_, 'infcx, 'tcx> {
     }
 
     pub(crate) fn temporary_value_borrowed_for_too_long(&self, span: Span) -> Diag<'infcx> {
-        struct_span_code_err!(self.dcx(), span, E0716, "temporary value dropped while borrowed",)
+        struct_span_code_err!(self.dcx(), span, E0716, "temporary value dropped while borrowed")
     }
 }
 
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 3b268f538cf..efb622e2155 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -2992,6 +2992,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         self.buffer_error(err);
     }
 
+    #[tracing::instrument(level = "debug", skip(self, explanation))]
     fn report_local_value_does_not_live_long_enough(
         &self,
         location: Location,
@@ -3001,13 +3002,6 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         borrow_spans: UseSpans<'tcx>,
         explanation: BorrowExplanation<'tcx>,
     ) -> Diag<'infcx> {
-        debug!(
-            "report_local_value_does_not_live_long_enough(\
-             {:?}, {:?}, {:?}, {:?}, {:?}\
-             )",
-            location, name, borrow, drop_span, borrow_spans
-        );
-
         let borrow_span = borrow_spans.var_or_use_path_span();
         if let BorrowExplanation::MustBeValidFor {
             category,
@@ -3031,15 +3025,6 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
 
         let mut err = self.path_does_not_live_long_enough(borrow_span, &name);
 
-        if let BorrowExplanation::MustBeValidFor { ref path, region_name, .. } = explanation {
-            for constraint in path {
-                if let ConstraintCategory::Predicate(pred) = constraint.category
-                    && !pred.is_dummy()
-                {
-                    err.span_note(pred, format!("requirement that {name} is borrowed for `{region_name}` introduced here"));
-                }
-            }
-        }
         if let Some(annotation) = self.annotate_argument_and_return_for_borrow(borrow) {
             let region_name = annotation.emit(self, &mut err);
 
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index 7ca07bb9b43..a0ea8b08556 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -416,6 +416,19 @@ impl<'tcx> BorrowExplanation<'tcx> {
                 {
                     self.add_object_lifetime_default_note(tcx, err, unsize_ty);
                 }
+
+                for constraint in path {
+                    if let ConstraintCategory::Predicate(pred) = constraint.category
+                        && !pred.is_dummy()
+                    {
+                        err.span_note(
+                            pred,
+                            format!("requirement for `{region_name}` introduced here"),
+                        );
+                        break;
+                    }
+                }
+
                 self.add_lifetime_bound_suggestion_to_diagnostic(err, &category, span, region_name);
             }
             _ => {}
diff --git a/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr b/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr
index e99ff763b9a..e0776c81dff 100644
--- a/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr
+++ b/tests/ui/async-await/async-closures/without-precise-captures-we-are-powerless.stderr
@@ -29,7 +29,7 @@ LL |     outlives::<'a>(call_once(c));
 LL | }
    | - `c` dropped here while still borrowed
    |
-note: requirement that `c` is borrowed for `'a` introduced here
+note: requirement for `'a` introduced here
   --> $DIR/without-precise-captures-we-are-powerless.rs:7:33
    |
 LL | fn outlives<'a>(_: impl Sized + 'a) {}
@@ -80,7 +80,7 @@ LL |     outlives::<'a>(call_once(c));
 LL | }
    | - `c` dropped here while still borrowed
    |
-note: requirement that `c` is borrowed for `'a` introduced here
+note: requirement for `'a` introduced here
   --> $DIR/without-precise-captures-we-are-powerless.rs:7:33
    |
 LL | fn outlives<'a>(_: impl Sized + 'a) {}
@@ -101,6 +101,12 @@ LL |     outlives::<'a>(c());
    |     argument requires that `c` is borrowed for `'a`
 LL |     outlives::<'a>(call_once(c));
    |                              ^ move out of `c` occurs here
+   |
+note: requirement for `'a` introduced here
+  --> $DIR/without-precise-captures-we-are-powerless.rs:7:33
+   |
+LL | fn outlives<'a>(_: impl Sized + 'a) {}
+   |                                 ^^
 
 error[E0597]: `x` does not live long enough
   --> $DIR/without-precise-captures-we-are-powerless.rs:36:13
@@ -142,7 +148,7 @@ LL |     outlives::<'a>(call_once(c));
 LL | }
    | - `c` dropped here while still borrowed
    |
-note: requirement that `c` is borrowed for `'a` introduced here
+note: requirement for `'a` introduced here
   --> $DIR/without-precise-captures-we-are-powerless.rs:7:33
    |
 LL | fn outlives<'a>(_: impl Sized + 'a) {}
@@ -190,7 +196,7 @@ LL |     T.outlives::<'a>(call_once(c));
 LL | }
    | - `c` dropped here while still borrowed
    |
-note: requirement that `c` is borrowed for `'a` introduced here
+note: requirement for `'a` introduced here
   --> $DIR/without-precise-captures-we-are-powerless.rs:49:47
    |
 LL |     fn outlives<'a>(&'a self, _: impl Sized + 'a) {}
diff --git a/tests/ui/borrowck/fn-item-check-type-params.stderr b/tests/ui/borrowck/fn-item-check-type-params.stderr
index aafb7e66ef5..8da0201134b 100644
--- a/tests/ui/borrowck/fn-item-check-type-params.stderr
+++ b/tests/ui/borrowck/fn-item-check-type-params.stderr
@@ -27,6 +27,12 @@ LL |     want(&String::new(), extend_lt);
    |     |     |
    |     |     creates a temporary value which is freed while still in use
    |     argument requires that borrow lasts for `'static`
+   |
+note: requirement for `'static` introduced here
+  --> $DIR/fn-item-check-type-params.rs:47:33
+   |
+LL |     fn want<I, O>(_: I, _: impl Fn(I) -> O) {}
+   |                                 ^^^^^^^^^^
 
 error[E0716]: temporary value dropped while borrowed
   --> $DIR/fn-item-check-type-params.rs:54:26
@@ -36,6 +42,12 @@ LL |     let val = extend_lt(&String::from("blah blah blah"));
    |               |          |
    |               |          creates a temporary value which is freed while still in use
    |               argument requires that borrow lasts for `'static`
+   |
+note: requirement for `'static` introduced here
+  --> $DIR/fn-item-check-type-params.rs:22:21
+   |
+LL |     (T, Option<U>): Displayable,
+   |                     ^^^^^^^^^^^
 
 error: aborting due to 4 previous errors
 
diff --git a/tests/ui/borrowck/implementation-not-general-enough-ice-133252.stderr b/tests/ui/borrowck/implementation-not-general-enough-ice-133252.stderr
index 393f7b1a61d..dab969586ef 100644
--- a/tests/ui/borrowck/implementation-not-general-enough-ice-133252.stderr
+++ b/tests/ui/borrowck/implementation-not-general-enough-ice-133252.stderr
@@ -23,7 +23,7 @@ LL |         force_send(async_load(&not_static));
 LL |     }
    |     - `not_static` dropped here while still borrowed
    |
-note: requirement that `not_static` is borrowed for `'1` introduced here
+note: requirement for `'1` introduced here
   --> $DIR/implementation-not-general-enough-ice-133252.rs:16:18
    |
 LL | fn force_send<T: Send>(_: T) {}
diff --git a/tests/ui/borrowck/issue-17545.stderr b/tests/ui/borrowck/issue-17545.stderr
index 45e977e3947..dc0a84b0ab4 100644
--- a/tests/ui/borrowck/issue-17545.stderr
+++ b/tests/ui/borrowck/issue-17545.stderr
@@ -10,6 +10,9 @@ LL | |     ));
    | |      -- temporary value is freed at the end of this statement
    | |______|
    |        argument requires that borrow lasts for `'a`
+   |
+note: requirement for `'a` introduced here
+  --> $SRC_DIR/core/src/ops/function.rs:LL:COL
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/generic-associated-types/bugs/hrtb-implied-1.stderr b/tests/ui/generic-associated-types/bugs/hrtb-implied-1.stderr
index 8bb72833e30..72f9a477daf 100644
--- a/tests/ui/generic-associated-types/bugs/hrtb-implied-1.stderr
+++ b/tests/ui/generic-associated-types/bugs/hrtb-implied-1.stderr
@@ -14,6 +14,11 @@ note: due to a current limitation of the type system, this implies a `'static` l
    |
 LL |     for<'a> I::Item<'a>: Debug,
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: requirement for `'static` introduced here
+  --> $DIR/hrtb-implied-1.rs:26:26
+   |
+LL |     for<'a> I::Item<'a>: Debug,
+   |                          ^^^^^
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/impl-trait/precise-capturing/migration-note.rs b/tests/ui/impl-trait/precise-capturing/migration-note.rs
index 25b594e9b1e..211def33320 100644
--- a/tests/ui/impl-trait/precise-capturing/migration-note.rs
+++ b/tests/ui/impl-trait/precise-capturing/migration-note.rs
@@ -32,7 +32,7 @@ fn needs_static() {
     //~| NOTE borrowed value does not live long enoug
 
     fn needs_static(_: impl Sized + 'static) {}
-    //~^ NOTE requirement that `x` is borrowed for `'static` introduced here
+    //~^ NOTE requirement for `'static` introduced here
     needs_static(a);
     //~^ NOTE argument requires that `x` is borrowed for `'static`
 }
@@ -80,7 +80,7 @@ fn needs_static_mut() {
     //~| NOTE borrowed value does not live long enough
 
     fn needs_static(_: impl Sized + 'static) {}
-    //~^ NOTE requirement that `x` is borrowed for `'static` introduced here
+    //~^ NOTE requirement for `'static` introduced here
     needs_static(a);
     //~^ NOTE argument requires that `x` is borrowed for `'static`
 }
diff --git a/tests/ui/impl-trait/precise-capturing/migration-note.stderr b/tests/ui/impl-trait/precise-capturing/migration-note.stderr
index e42a6f15c7e..c06b14a4113 100644
--- a/tests/ui/impl-trait/precise-capturing/migration-note.stderr
+++ b/tests/ui/impl-trait/precise-capturing/migration-note.stderr
@@ -50,7 +50,7 @@ LL |
 LL | }
    | - `x` dropped here while still borrowed
    |
-note: requirement that `x` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/migration-note.rs:34:37
    |
 LL |     fn needs_static(_: impl Sized + 'static) {}
@@ -131,7 +131,7 @@ LL |
 LL | }
    | - `x` dropped here while still borrowed
    |
-note: requirement that `x` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/migration-note.rs:82:37
    |
 LL |     fn needs_static(_: impl Sized + 'static) {}
diff --git a/tests/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr b/tests/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr
index 136da57daec..eb110e868aa 100644
--- a/tests/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr
+++ b/tests/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr
@@ -70,7 +70,7 @@ LL |     })
 LL | }
    | - `a` dropped here while still borrowed
    |
-note: requirement that `a` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:13:8
    |
 LL |     F: for<'x> FnOnce(Cell<&'a u32>, Cell<&'x u32>),
diff --git a/tests/ui/nll/closure-requirements/propagate-multiple-requirements.stderr b/tests/ui/nll/closure-requirements/propagate-multiple-requirements.stderr
index 8e18f546ebd..51e4d77c91a 100644
--- a/tests/ui/nll/closure-requirements/propagate-multiple-requirements.stderr
+++ b/tests/ui/nll/closure-requirements/propagate-multiple-requirements.stderr
@@ -14,7 +14,7 @@ LL |         z = &local_arr;
 LL | }
    | - `local_arr` dropped here while still borrowed
    |
-note: requirement that `local_arr` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/propagate-multiple-requirements.rs:4:21
    |
 LL | fn once<S, T, U, F: FnOnce(S, T) -> U>(f: F, s: S, t: T) -> U {
diff --git a/tests/ui/nll/local-outlives-static-via-hrtb.stderr b/tests/ui/nll/local-outlives-static-via-hrtb.stderr
index cc01a3cfc0b..ff2be3a2b28 100644
--- a/tests/ui/nll/local-outlives-static-via-hrtb.stderr
+++ b/tests/ui/nll/local-outlives-static-via-hrtb.stderr
@@ -12,16 +12,16 @@ LL |     assert_static_via_hrtb_with_assoc_type(&&local);
 LL | }
    | - `local` dropped here while still borrowed
    |
-note: requirement that `local` is borrowed for `'static` introduced here
-  --> $DIR/local-outlives-static-via-hrtb.rs:15:53
-   |
-LL | fn assert_static_via_hrtb<G>(_: G) where for<'a> G: Outlives<'a> {}
-   |                                                     ^^^^^^^^^^^^
 note: due to a current limitation of the type system, this implies a `'static` lifetime
   --> $DIR/local-outlives-static-via-hrtb.rs:15:42
    |
 LL | fn assert_static_via_hrtb<G>(_: G) where for<'a> G: Outlives<'a> {}
    |                                          ^^^^^^^^^^^^^^^^^^^^^^^
+note: requirement for `'static` introduced here
+  --> $DIR/local-outlives-static-via-hrtb.rs:15:53
+   |
+LL | fn assert_static_via_hrtb<G>(_: G) where for<'a> G: Outlives<'a> {}
+   |                                                     ^^^^^^^^^^^^
 
 error[E0597]: `local` does not live long enough
   --> $DIR/local-outlives-static-via-hrtb.rs:25:45
@@ -37,16 +37,16 @@ LL |     assert_static_via_hrtb_with_assoc_type(&&local);
 LL | }
    | - `local` dropped here while still borrowed
    |
-note: requirement that `local` is borrowed for `'static` introduced here
-  --> $DIR/local-outlives-static-via-hrtb.rs:19:30
-   |
-LL |     for<'a> &'a T: Reference<AssociatedType = &'a ()>,
-   |                              ^^^^^^^^^^^^^^^^^^^^^^^
 note: due to a current limitation of the type system, this implies a `'static` lifetime
   --> $DIR/local-outlives-static-via-hrtb.rs:19:5
    |
 LL |     for<'a> &'a T: Reference<AssociatedType = &'a ()>,
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: requirement for `'static` introduced here
+  --> $DIR/local-outlives-static-via-hrtb.rs:19:30
+   |
+LL |     for<'a> &'a T: Reference<AssociatedType = &'a ()>,
+   |                              ^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 2 previous errors
 
diff --git a/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.nll.stderr b/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.nll.stderr
index 56ad78ba4b4..fdc3fc059c5 100644
--- a/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.nll.stderr
+++ b/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.nll.stderr
@@ -13,16 +13,16 @@ LL |     let b = |_| &a;
 LL | }
    | - `a` dropped here while still borrowed
    |
-note: requirement that `a` is borrowed for `'static` introduced here
-  --> $DIR/location-insensitive-scopes-issue-117146.rs:20:22
-   |
-LL | fn bad<F: Fn(&()) -> &()>(_: F) {}
-   |                      ^^^
 note: due to a current limitation of the type system, this implies a `'static` lifetime
   --> $DIR/location-insensitive-scopes-issue-117146.rs:20:11
    |
 LL | fn bad<F: Fn(&()) -> &()>(_: F) {}
    |           ^^^^^^^^^^^^^^
+note: requirement for `'static` introduced here
+  --> $DIR/location-insensitive-scopes-issue-117146.rs:20:22
+   |
+LL | fn bad<F: Fn(&()) -> &()>(_: F) {}
+   |                      ^^^
 
 error: implementation of `Fn` is not general enough
   --> $DIR/location-insensitive-scopes-issue-117146.rs:13:5
diff --git a/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.polonius.stderr b/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.polonius.stderr
index 56ad78ba4b4..fdc3fc059c5 100644
--- a/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.polonius.stderr
+++ b/tests/ui/nll/polonius/location-insensitive-scopes-issue-117146.polonius.stderr
@@ -13,16 +13,16 @@ LL |     let b = |_| &a;
 LL | }
    | - `a` dropped here while still borrowed
    |
-note: requirement that `a` is borrowed for `'static` introduced here
-  --> $DIR/location-insensitive-scopes-issue-117146.rs:20:22
-   |
-LL | fn bad<F: Fn(&()) -> &()>(_: F) {}
-   |                      ^^^
 note: due to a current limitation of the type system, this implies a `'static` lifetime
   --> $DIR/location-insensitive-scopes-issue-117146.rs:20:11
    |
 LL | fn bad<F: Fn(&()) -> &()>(_: F) {}
    |           ^^^^^^^^^^^^^^
+note: requirement for `'static` introduced here
+  --> $DIR/location-insensitive-scopes-issue-117146.rs:20:22
+   |
+LL | fn bad<F: Fn(&()) -> &()>(_: F) {}
+   |                      ^^^
 
 error: implementation of `Fn` is not general enough
   --> $DIR/location-insensitive-scopes-issue-117146.rs:13:5
diff --git a/tests/ui/regions/regions-infer-proc-static-upvar.stderr b/tests/ui/regions/regions-infer-proc-static-upvar.stderr
index 1a76b5f00f9..ff833de0ad0 100644
--- a/tests/ui/regions/regions-infer-proc-static-upvar.stderr
+++ b/tests/ui/regions/regions-infer-proc-static-upvar.stderr
@@ -12,7 +12,7 @@ LL | |     });
 LL |   }
    |   - `x` dropped here while still borrowed
    |
-note: requirement that `x` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/regions-infer-proc-static-upvar.rs:4:19
    |
 LL | fn foo<F:FnOnce()+'static>(_p: F) { }
diff --git a/tests/ui/regions/regions-pattern-typing-issue-19552.stderr b/tests/ui/regions/regions-pattern-typing-issue-19552.stderr
index 2c8ce20f09e..76cd18dfa13 100644
--- a/tests/ui/regions/regions-pattern-typing-issue-19552.stderr
+++ b/tests/ui/regions/regions-pattern-typing-issue-19552.stderr
@@ -11,7 +11,7 @@ LL |     }
 LL | }
    | - `line` dropped here while still borrowed
    |
-note: requirement that `line` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/regions-pattern-typing-issue-19552.rs:1:21
    |
 LL | fn assert_static<T: 'static>(_t: T) {}
diff --git a/tests/ui/static/static-lifetime-bound.stderr b/tests/ui/static/static-lifetime-bound.stderr
index e530e4669d7..354a1327bee 100644
--- a/tests/ui/static/static-lifetime-bound.stderr
+++ b/tests/ui/static/static-lifetime-bound.stderr
@@ -11,7 +11,7 @@ LL |     f(&x);
 LL | }
    | - `x` dropped here while still borrowed
    |
-note: requirement that `x` is borrowed for `'static` introduced here
+note: requirement for `'static` introduced here
   --> $DIR/static-lifetime-bound.rs:1:10
    |
 LL | fn f<'a: 'static>(_: &'a i32) {}
diff --git a/tests/ui/static/static-region-bound.stderr b/tests/ui/static/static-region-bound.stderr
index a47c9457102..e7747216a57 100644
--- a/tests/ui/static/static-region-bound.stderr
+++ b/tests/ui/static/static-region-bound.stderr
@@ -7,6 +7,12 @@ LL |     f(x);
    |     ---- argument requires that borrow lasts for `'static`
 LL | }
    | - temporary value is freed at the end of this statement
+   |
+note: requirement for `'static` introduced here
+  --> $DIR/static-region-bound.rs:3:8
+   |
+LL | fn f<T:'static>(_: T) {}
+   |        ^^^^^^^
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/wf/wf-in-where-clause-static.current.stderr b/tests/ui/wf/wf-in-where-clause-static.current.stderr
index d0bb89884c6..53cc6093f54 100644
--- a/tests/ui/wf/wf-in-where-clause-static.current.stderr
+++ b/tests/ui/wf/wf-in-where-clause-static.current.stderr
@@ -6,6 +6,12 @@ LL |     let s = foo(&String::from("blah blah blah"));
    |             |    |
    |             |    creates a temporary value which is freed while still in use
    |             argument requires that borrow lasts for `'static`
+   |
+note: requirement for `'static` introduced here
+  --> $DIR/wf-in-where-clause-static.rs:12:17
+   |
+LL |     &'static S: Static,
+   |                 ^^^^^^
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/wf/wf-in-where-clause-static.next.stderr b/tests/ui/wf/wf-in-where-clause-static.next.stderr
index d0bb89884c6..53cc6093f54 100644
--- a/tests/ui/wf/wf-in-where-clause-static.next.stderr
+++ b/tests/ui/wf/wf-in-where-clause-static.next.stderr
@@ -6,6 +6,12 @@ LL |     let s = foo(&String::from("blah blah blah"));
    |             |    |
    |             |    creates a temporary value which is freed while still in use
    |             argument requires that borrow lasts for `'static`
+   |
+note: requirement for `'static` introduced here
+  --> $DIR/wf-in-where-clause-static.rs:12:17
+   |
+LL |     &'static S: Static,
+   |                 ^^^^^^
 
 error: aborting due to 1 previous error