Always look at the trait bounds (not just when looking at a trait DefId)

Author: estebank

compiler/rustc_borrowck/src/diagnostics/region_errors.rs

@@ -634,7 +634,9 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         let mut parent = tcx.parent(def_id);
         debug!(?def_id, ?parent);
         let trait_preds = match tcx.def_kind(parent) {
-            hir::def::DefKind::Impl { .. } => &[],
+            hir::def::DefKind::Impl { .. } => {
+                tcx.trait_id_of_impl(parent).map_or(&[][..], |id| tcx.predicates_of(id).predicates)
+            }
             hir::def::DefKind::Trait => {
                 let Some(ty) = args.get(0).and_then(|arg| arg.as_type()) else {
                     return;

tests/ui/lifetimes/static-impl-obligation.rs

@@ -272,8 +272,8 @@ mod w {
 
     }
     fn convert<'a>(x: &'a &'a u32) {
-        let y: &dyn Foo = x; //~ ERROR lifetime may not live long enough
-        y.hello();
+        let y: &dyn Foo = x;
+        y.hello(); //~ ERROR lifetime may not live long enough
     }
 }
 fn main() {}

tests/ui/lifetimes/static-impl-obligation.stderr

@@ -438,12 +438,20 @@ LL |     impl Trait for dyn Foo + '_ {
    |                            ++++
 
 error: lifetime may not live long enough
-  --> $DIR/static-impl-obligation.rs:275:27
+  --> $DIR/static-impl-obligation.rs:276:9
    |
 LL |     fn convert<'a>(x: &'a &'a u32) {
    |                -- lifetime `'a` defined here
 LL |         let y: &dyn Foo = x;
-   |                           ^ cast requires that `'a` must outlive `'static`
+   |                           - cast requires that `'a` must outlive `'static`
+LL |         y.hello();
+   |         ^^^^^^^^^ calling this method introduces a `'static` lifetime requirement
+   |
+note: the `impl` on `dyn w::Foo` has a `'static` lifetime requirement
+  --> $DIR/static-impl-obligation.rs:268:29
+   |
+LL |     trait Trait where Self: 'static { fn hello(&self) {} }
+   |                             ^^^^^^^
 
 error: aborting due to 25 previous errors