Consider patterns in fn params in an Elided(Infer) lifetime rib.

Author: cjgillot

compiler/rustc_resolve/src/late.rs

@@ -1853,9 +1853,11 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
         let mut bindings = smallvec![(PatBoundCtx::Product, Default::default())];
         for (index, (pat, ty)) in inputs.enumerate() {
             debug!(?pat, ?ty);
-            if let Some(pat) = pat {
-                self.resolve_pattern(pat, PatternSource::FnParam, &mut bindings);
-            }
+            self.with_lifetime_rib(LifetimeRibKind::Elided(LifetimeRes::Infer), |this| {
+                if let Some(pat) = pat {
+                    this.resolve_pattern(pat, PatternSource::FnParam, &mut bindings);
+                }
+            });
             self.visit_ty(ty);
 
             if let Some(ref candidates) = self.lifetime_elision_candidates {
@@ -2827,10 +2829,13 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
 
     fn resolve_params(&mut self, params: &'ast [Param]) {
         let mut bindings = smallvec![(PatBoundCtx::Product, Default::default())];
-        for Param { pat, ty, .. } in params {
-            self.resolve_pattern(pat, PatternSource::FnParam, &mut bindings);
+        self.with_lifetime_rib(LifetimeRibKind::Elided(LifetimeRes::Infer), |this| {
+            for Param { pat, .. } in params {
+                this.resolve_pattern(pat, PatternSource::FnParam, &mut bindings);
+            }
+        });
+        for Param { ty, .. } in params {
             self.visit_ty(ty);
-            debug!("(resolving function / closure) recorded parameter");
         }
     }
 

src/test/ui/lifetimes/elided-lifetime-in-param-pat.rs

@@ -0,0 +1,11 @@
+// check-pass
+
+struct S<T> {
+    _t: T,
+}
+
+fn f(S::<&i8> { .. }: S<&i8>) {}
+
+fn main() {
+    f(S { _t: &42_i8 });
+}