Rollup merge of rust-lang#64250 - Xanewok:save-analysis-assoc-nested, r=varkor

save-analysis: Nest typeck tables when processing functions/methods

Fixes an issue where we did not nest tables correctly when resolving
associated types in formal argument/return type positions.

This was the minimized reproduction case that I tested the fix on:
```rust
pub trait Trait {
    type Assoc;
}

pub struct A;

pub fn func() {
    fn _inner1<U: Trait>(_: U::Assoc) {}
    fn _inner2<U: Trait>() -> U::Assoc { unimplemented!() }

    impl A {
        fn _inner1<U: Trait>(self, _: U::Assoc) {}
        fn _inner2<U: Trait>(self) -> U::Assoc { unimplemented!() }
    }
}
```
using `debug_assertions`-enabled rustc and by additionally passing `-Zsave-analysis`.

Unfortunately the original assertion fired is a *debug* one and from what I can tell we don't run the tests with these on, so I'm not adding a test here. If I missed it and there is a way to run tests with these on, I'd love to add a test case for this.

Closes rust-lang#63663
Closes rust-lang#50328
Closes rust-lang#43982

Author: tmandry

src/librustc/ty/context.rs

@@ -205,26 +205,24 @@ pub struct LocalTableInContext<'a, V> {
 fn validate_hir_id_for_typeck_tables(local_id_root: Option<DefId>,
                                      hir_id: hir::HirId,
                                      mut_access: bool) {
-    if cfg!(debug_assertions) {
-        if let Some(local_id_root) = local_id_root {
-            if hir_id.owner != local_id_root.index {
-                ty::tls::with(|tcx| {
-                    bug!("node {} with HirId::owner {:?} cannot be placed in \
-                          TypeckTables with local_id_root {:?}",
-                         tcx.hir().node_to_string(hir_id),
-                         DefId::local(hir_id.owner),
-                         local_id_root)
-                });
-            }
-        } else {
-            // We use "Null Object" TypeckTables in some of the analysis passes.
-            // These are just expected to be empty and their `local_id_root` is
-            // `None`. Therefore we cannot verify whether a given `HirId` would
-            // be a valid key for the given table. Instead we make sure that
-            // nobody tries to write to such a Null Object table.
-            if mut_access {
-                bug!("access to invalid TypeckTables")
-            }
+    if let Some(local_id_root) = local_id_root {
+        if hir_id.owner != local_id_root.index {
+            ty::tls::with(|tcx| {
+                bug!("node {} with HirId::owner {:?} cannot be placed in \
+                        TypeckTables with local_id_root {:?}",
+                        tcx.hir().node_to_string(hir_id),
+                        DefId::local(hir_id.owner),
+                        local_id_root)
+            });
+        }
+    } else {
+        // We use "Null Object" TypeckTables in some of the analysis passes.
+        // These are just expected to be empty and their `local_id_root` is
+        // `None`. Therefore we cannot verify whether a given `HirId` would
+        // be a valid key for the given table. Instead we make sure that
+        // nobody tries to write to such a Null Object table.
+        if mut_access {
+            bug!("access to invalid TypeckTables")
         }
     }
 }

src/librustc_save_analysis/dump_visitor.rs

@@ -283,36 +283,32 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
     ) {
         debug!("process_method: {}:{}", id, ident);
 
-        if let Some(mut method_data) = self.save_ctxt.get_method_data(id, ident, span) {
-            let sig_str = crate::make_signature(&sig.decl, &generics);
-            if body.is_some() {
-                self.nest_tables(
-                    id,
-                    |v| v.process_formals(&sig.decl.inputs, &method_data.qualname),
-                );
-            }
+        let hir_id = self.tcx.hir().node_to_hir_id(id);
+        self.nest_tables(id, |v| {
+            if let Some(mut method_data) = v.save_ctxt.get_method_data(id, ident, span) {
+                v.process_formals(&sig.decl.inputs, &method_data.qualname);
+                v.process_generic_params(&generics, &method_data.qualname, id);
 
-            self.process_generic_params(&generics, &method_data.qualname, id);
+                method_data.value = crate::make_signature(&sig.decl, &generics);
+                method_data.sig = sig::method_signature(id, ident, generics, sig, &v.save_ctxt);
 
-            method_data.value = sig_str;
-            method_data.sig = sig::method_signature(id, ident, generics, sig, &self.save_ctxt);
-            let hir_id = self.tcx.hir().node_to_hir_id(id);
-            self.dumper.dump_def(&access_from_vis!(self.save_ctxt, vis, hir_id), method_data);
-        }
+                v.dumper.dump_def(&access_from_vis!(v.save_ctxt, vis, hir_id), method_data);
+            }
 
-        // walk arg and return types
-        for arg in &sig.decl.inputs {
-            self.visit_ty(&arg.ty);
-        }
+            // walk arg and return types
+            for arg in &sig.decl.inputs {
+                v.visit_ty(&arg.ty);
+            }
 
-        if let ast::FunctionRetTy::Ty(ref ret_ty) = sig.decl.output {
-            self.visit_ty(ret_ty);
-        }
+            if let ast::FunctionRetTy::Ty(ref ret_ty) = sig.decl.output {
+                v.visit_ty(ret_ty);
+            }
 
-        // walk the fn body
-        if let Some(body) = body {
-            self.nest_tables(id, |v| v.visit_block(body));
-        }
+            // walk the fn body
+            if let Some(body) = body {
+                v.visit_block(body);
+            }
+        });
     }
 
     fn process_struct_field_def(&mut self, field: &ast::StructField, parent_id: NodeId) {
@@ -377,26 +373,26 @@ impl<'l, 'tcx> DumpVisitor<'l, 'tcx> {
         ty_params: &'l ast::Generics,
         body: &'l ast::Block,
     ) {
-        if let Some(fn_data) = self.save_ctxt.get_item_data(item) {
-            down_cast_data!(fn_data, DefData, item.span);
-            self.nest_tables(
-                item.id,
-                |v| v.process_formals(&decl.inputs, &fn_data.qualname),
-            );
-            self.process_generic_params(ty_params, &fn_data.qualname, item.id);
-            let hir_id = self.tcx.hir().node_to_hir_id(item.id);
-            self.dumper.dump_def(&access_from!(self.save_ctxt, item, hir_id), fn_data);
-        }
+        let hir_id = self.tcx.hir().node_to_hir_id(item.id);
+        self.nest_tables(item.id, |v| {
+            if let Some(fn_data) = v.save_ctxt.get_item_data(item) {
+                down_cast_data!(fn_data, DefData, item.span);
+                v.process_formals(&decl.inputs, &fn_data.qualname);
+                v.process_generic_params(ty_params, &fn_data.qualname, item.id);
 
-        for arg in &decl.inputs {
-            self.visit_ty(&arg.ty);
-        }
+                v.dumper.dump_def(&access_from!(v.save_ctxt, item, hir_id), fn_data);
+            }
 
-        if let ast::FunctionRetTy::Ty(ref ret_ty) = decl.output {
-            self.visit_ty(&ret_ty);
-        }
+            for arg in &decl.inputs {
+                v.visit_ty(&arg.ty)
+            }
 
-        self.nest_tables(item.id, |v| v.visit_block(&body));
+            if let ast::FunctionRetTy::Ty(ref ret_ty) = decl.output {
+                v.visit_ty(&ret_ty);
+            }
+
+            v.visit_block(&body);
+        });
     }
 
     fn process_static_or_const_item(

src/test/ui/save-analysis/issue-63663.rs

@@ -0,0 +1,23 @@
+// check-pass
+// compile-flags: -Zsave-analysis
+
+// Check that this doesn't ICE when processing associated const in formal
+// argument and return type of functions defined inside function/method scope.
+
+pub trait Trait {
+    type Assoc;
+}
+
+pub struct A;
+
+pub fn func() {
+    fn _inner1<U: Trait>(_: U::Assoc) {}
+    fn _inner2<U: Trait>() -> U::Assoc { unimplemented!() }
+
+    impl A {
+        fn _inner1<U: Trait>(self, _: U::Assoc) {}
+        fn _inner2<U: Trait>(self) -> U::Assoc { unimplemented!() }
+    }
+}
+
+fn main() {}