TypeVerifier do not walk into required consts

Author: lcnr

Diff for: compiler/rustc_borrowck/src/type_check/mod.rs

@@ -328,9 +328,8 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
         }
     }
 
+    #[instrument(level = "debug", skip(self))]
     fn visit_const_operand(&mut self, constant: &ConstOperand<'tcx>, location: Location) {
-        debug!(?constant, ?location, "visit_const_operand");
-
         self.super_const_operand(constant, location);
         let ty = constant.const_.ty();
 
@@ -339,14 +338,7 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
             self.typeck.constraints.liveness_constraints.add_location(live_region_vid, location);
         });
 
-        // HACK(compiler-errors): Constants that are gathered into Body.required_consts
-        // have their locations erased...
-        let locations = if location != Location::START {
-            location.to_locations()
-        } else {
-            Locations::All(constant.span)
-        };
-
+        let locations = location.to_locations();
         if let Some(annotation_index) = constant.user_ty {
             if let Err(terr) = self.typeck.relate_type_and_user_type(
                 constant.const_.ty(),
@@ -491,9 +483,28 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
         }
     }
 
+    #[instrument(level = "debug", skip(self))]
     fn visit_body(&mut self, body: &Body<'tcx>) {
-        // The types of local_decls are checked above which is called in super_body.
-        self.super_body(body);
+        // We intentionally do not recursive into `body.required_consts` or
+        // `body.mentioned_items` here as the MIR at this phase should still
+        // refer to all items and we don't want to check them multiple times.
+
+        for (local, local_decl) in body.local_decls.iter_enumerated() {
+            self.visit_local_decl(local, local_decl);
+        }
+
+        for (block, block_data) in body.basic_blocks.iter_enumerated() {
+            let mut location = Location { block, statement_index: 0 };
+            for stmt in &block_data.statements {
+                if !stmt.source_info.span.is_dummy() {
+                    self.last_span = stmt.source_info.span;
+                }
+                self.visit_statement(stmt, location);
+                location.statement_index += 1;
+            }
+
+            self.visit_terminator(block_data.terminator(), location);
+        }
     }
 }
 

Diff for: tests/ui/error-codes/E0582.stderr

@@ -14,7 +14,7 @@ error[E0308]: mismatched types
   --> $DIR/E0582.rs:22:5
    |
 LL |     bar(mk_unexpected_char_err)
-   |     ^^^ one type is more general than the other
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
    |
    = note: expected enum `Option<&_>`
               found enum `Option<&'a _>`

Diff for: tests/ui/higher-ranked/trait-bounds/hrtb-just-for-static.stderr

@@ -2,7 +2,7 @@ error: implementation of `Foo` is not general enough
   --> $DIR/hrtb-just-for-static.rs:24:5
    |
 LL |     want_hrtb::<StaticInt>()
-   |     ^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
    |
    = note: `StaticInt` must implement `Foo<&'0 isize>`, for any lifetime `'0`...
    = note: ...but it actually implements `Foo<&'static isize>`

Diff for: tests/ui/nll/issue-97997.rs

@@ -12,5 +12,4 @@ fn main() {
 
     <fn(&u8) as Foo>::ASSOC;
     //~^ ERROR implementation of `Foo` is not general enough
-    //~| ERROR implementation of `Foo` is not general enough
 }

Diff for: tests/ui/nll/issue-97997.stderr

@@ -7,15 +7,5 @@ LL |     <fn(&u8) as Foo>::ASSOC;
    = note: `Foo` would have to be implemented for the type `for<'a> fn(&'a u8)`
    = note: ...but `Foo` is actually implemented for the type `fn(&'0 u8)`, for some specific lifetime `'0`
 
-error: implementation of `Foo` is not general enough
-  --> $DIR/issue-97997.rs:13:5
-   |
-LL |     <fn(&u8) as Foo>::ASSOC;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^ implementation of `Foo` is not general enough
-   |
-   = note: `Foo` would have to be implemented for the type `for<'a> fn(&'a u8)`
-   = note: ...but `Foo` is actually implemented for the type `fn(&'0 u8)`, for some specific lifetime `'0`
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 

Diff for: tests/ui/type-alias-impl-trait/implied_lifetime_wf_check3.stderr

@@ -28,7 +28,7 @@ error[E0310]: the parameter type `A` may not live long enough
   --> $DIR/implied_lifetime_wf_check3.rs:52:5
    |
 LL |     test_type_param::assert_static::<A>()
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |     |
    |     the parameter type `A` must be valid for the static lifetime...
    |     ...so that the type `A` will meet its required lifetime bounds

Diff for: tests/ui/type-alias-impl-trait/implied_lifetime_wf_check4_static.stderr

@@ -21,7 +21,7 @@ error[E0310]: the parameter type `A` may not live long enough
   --> $DIR/implied_lifetime_wf_check4_static.rs:17:5
    |
 LL |     assert_static::<A>()
-   |     ^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^
    |     |
    |     the parameter type `A` must be valid for the static lifetime...
    |     ...so that the type `A` will meet its required lifetime bounds