Auto merge of #124902 - compiler-errors:mem-cat-but-better, r=lcnr

Fix MemCategorization and ExprUse visitors for new solver (this time it's better)

Best reviewed by each commit. Supersedes #124859.

r? lcnr

Author: bors

clippy_lints/src/escape.rs

@@ -1,7 +1,6 @@
 use clippy_utils::diagnostics::span_lint_hir;
 use rustc_hir::{intravisit, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node, Pat, PatKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::layout::LayoutOf;
@@ -105,8 +104,7 @@ impl<'tcx> LateLintPass<'tcx> for BoxedLocal {
             too_large_for_stack: self.too_large_for_stack,
         };
 
-        let infcx = cx.tcx.infer_ctxt().build();
-        ExprUseVisitor::new(&mut v, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
+        ExprUseVisitor::for_clippy(cx, fn_def_id, &mut v).consume_body(body).into_ok();
 
         for node in v.set {
             span_lint_hir(

clippy_lints/src/lib.rs

@@ -8,6 +8,7 @@
 #![feature(never_type)]
 #![feature(rustc_private)]
 #![feature(stmt_expr_attributes)]
+#![feature(unwrap_infallible)]
 #![recursion_limit = "512"]
 #![cfg_attr(feature = "deny-warnings", deny(warnings))]
 #![allow(

clippy_lints/src/loops/mut_range_bound.rs

@@ -4,7 +4,6 @@ use clippy_utils::{get_enclosing_block, higher, path_to_local};
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{BindingMode, Expr, ExprKind, HirId, Node, PatKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::LateContext;
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty;
@@ -61,15 +60,12 @@ fn check_for_mutation(
         span_low: None,
         span_high: None,
     };
-    let infcx = cx.tcx.infer_ctxt().build();
-    ExprUseVisitor::new(
-        &mut delegate,
-        &infcx,
+    ExprUseVisitor::for_clippy(
+        cx,
         body.hir_id.owner.def_id,
-        cx.param_env,
-        cx.typeck_results(),
+        &mut delegate,
     )
-    .walk_expr(body);
+    .walk_expr(body).into_ok();
 
     delegate.mutation_span()
 }

clippy_lints/src/methods/iter_overeager_cloned.rs

@@ -9,7 +9,6 @@ use rustc_lint::LateContext;
 use rustc_middle::mir::{FakeReadCause, Mutability};
 use rustc_middle::ty::{self, BorrowKind};
 use rustc_span::sym;
-use rustc_trait_selection::infer::TyCtxtInferExt;
 
 use super::ITER_OVEREAGER_CLONED;
 use crate::redundant_clone::REDUNDANT_CLONE;
@@ -69,16 +68,13 @@ pub(super) fn check<'tcx>(
             let mut delegate = MoveDelegate {
                 used_move: HirIdSet::default(),
             };
-            let infcx = cx.tcx.infer_ctxt().build();
 
-            ExprUseVisitor::new(
+            ExprUseVisitor::for_clippy(
+                cx,
+                closure.def_id,
                 &mut delegate,
-                &infcx,
-                closure.body.hir_id.owner.def_id,
-                cx.param_env,
-                cx.typeck_results(),
             )
-            .consume_body(body);
+            .consume_body(body).into_ok();
 
             let mut to_be_discarded = false;
 

clippy_lints/src/needless_pass_by_ref_mut.rs

@@ -11,7 +11,6 @@ use rustc_hir::{
     PatKind,
 };
 use rustc_hir_typeck::expr_use_visitor as euv;
-use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, Ty, TyCtxt, UpvarId, UpvarPath};
@@ -102,7 +101,6 @@ fn should_skip<'tcx>(
 fn check_closures<'tcx>(
     ctx: &mut MutablyUsedVariablesCtxt<'tcx>,
     cx: &LateContext<'tcx>,
-    infcx: &InferCtxt<'tcx>,
     checked_closures: &mut FxHashSet<LocalDefId>,
     closures: FxHashSet<LocalDefId>,
 ) {
@@ -119,7 +117,7 @@ fn check_closures<'tcx>(
             .associated_body()
             .map(|(_, body_id)| hir.body(body_id))
         {
-            euv::ExprUseVisitor::new(ctx, infcx, closure, cx.param_env, cx.typeck_results()).consume_body(body);
+            euv::ExprUseVisitor::for_clippy(cx, closure, &mut *ctx).consume_body(body).into_ok();
         }
     }
 }
@@ -196,8 +194,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByRefMut<'tcx> {
                 async_closures: FxHashSet::default(),
                 tcx: cx.tcx,
             };
-            let infcx = cx.tcx.infer_ctxt().build();
-            euv::ExprUseVisitor::new(&mut ctx, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
+            euv::ExprUseVisitor::for_clippy(cx, fn_def_id, &mut ctx).consume_body(body).into_ok();
 
             let mut checked_closures = FxHashSet::default();
 
@@ -210,13 +207,13 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByRefMut<'tcx> {
                 }
                 ControlFlow::<()>::Continue(())
             });
-            check_closures(&mut ctx, cx, &infcx, &mut checked_closures, closures);
+            check_closures(&mut ctx, cx, &mut checked_closures, closures);
 
             if is_async {
                 while !ctx.async_closures.is_empty() {
                     let async_closures = ctx.async_closures.clone();
                     ctx.async_closures.clear();
-                    check_closures(&mut ctx, cx, &infcx, &mut checked_closures, async_closures);
+                    check_closures(&mut ctx, cx, &mut checked_closures, async_closures);
                 }
             }
             ctx.generate_mutably_used_ids_from_aliases()

clippy_lints/src/needless_pass_by_value.rs

@@ -13,7 +13,6 @@ use rustc_hir::{
     TyKind,
 };
 use rustc_hir_typeck::expr_use_visitor as euv;
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{self, Ty, TypeVisitableExt};
@@ -134,8 +133,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
         // function body.
         let MovedVariablesCtxt { moved_vars } = {
             let mut ctx = MovedVariablesCtxt::default();
-            let infcx = cx.tcx.infer_ctxt().build();
-            euv::ExprUseVisitor::new(&mut ctx, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body);
+            euv::ExprUseVisitor::for_clippy(cx, fn_def_id, &mut ctx).consume_body(body).into_ok();
             ctx
         };
 

clippy_lints/src/operators/assign_op_pattern.rs

@@ -11,7 +11,6 @@ use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, Pl
 use rustc_lint::LateContext;
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::BorrowKind;
-use rustc_trait_selection::infer::TyCtxtInferExt;
 
 use super::ASSIGN_OP_PATTERN;
 
@@ -119,15 +118,8 @@ fn imm_borrows_in_expr(cx: &LateContext<'_>, e: &hir::Expr<'_>) -> HirIdSet {
     }
 
     let mut s = S(HirIdSet::default());
-    let infcx = cx.tcx.infer_ctxt().build();
-    let mut v = ExprUseVisitor::new(
-        &mut s,
-        &infcx,
-        cx.tcx.hir().body_owner_def_id(cx.enclosing_body.unwrap()),
-        cx.param_env,
-        cx.typeck_results(),
-    );
-    v.consume_expr(e);
+    let v = ExprUseVisitor::for_clippy(cx, e.hir_id.owner.def_id, &mut s);
+    v.consume_expr(e).into_ok();
     s.0
 }
 
@@ -151,14 +143,7 @@ fn mut_borrows_in_expr(cx: &LateContext<'_>, e: &hir::Expr<'_>) -> HirIdSet {
     }
 
     let mut s = S(HirIdSet::default());
-    let infcx = cx.tcx.infer_ctxt().build();
-    let mut v = ExprUseVisitor::new(
-        &mut s,
-        &infcx,
-        cx.tcx.hir().body_owner_def_id(cx.enclosing_body.unwrap()),
-        cx.param_env,
-        cx.typeck_results(),
-    );
-    v.consume_expr(e);
+    let v = ExprUseVisitor::for_clippy(cx, e.hir_id.owner.def_id, &mut s);
+    v.consume_expr(e).into_ok();
     s.0
 }

clippy_lints/src/unwrap.rs

@@ -6,7 +6,6 @@ use rustc_errors::Applicability;
 use rustc_hir::intravisit::{walk_expr, walk_fn, FnKind, Visitor};
 use rustc_hir::{BinOpKind, Body, Expr, ExprKind, FnDecl, HirId, Node, PathSegment, UnOp};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter;
 use rustc_middle::lint::in_external_macro;
@@ -252,16 +251,13 @@ impl<'a, 'tcx> UnwrappableVariablesVisitor<'a, 'tcx> {
                 local_id: unwrap_info.local_id,
             };
 
-            let infcx = self.cx.tcx.infer_ctxt().build();
-            let mut vis = ExprUseVisitor::new(
-                &mut delegate,
-                &infcx,
+            let vis = ExprUseVisitor::for_clippy(
+                self.cx,
                 cond.hir_id.owner.def_id,
-                self.cx.param_env,
-                self.cx.typeck_results(),
+                &mut delegate,
             );
-            vis.walk_expr(cond);
-            vis.walk_expr(branch);
+            vis.walk_expr(cond).into_ok();
+            vis.walk_expr(branch).into_ok();
 
             if delegate.is_mutated {
                 // if the variable is mutated, we don't know whether it can be unwrapped.

clippy_utils/src/lib.rs

@@ -7,6 +7,7 @@
 #![feature(never_type)]
 #![feature(rustc_private)]
 #![feature(assert_matches)]
+#![feature(unwrap_infallible)]
 #![recursion_limit = "512"]
 #![cfg_attr(feature = "deny-warnings", deny(warnings))]
 #![allow(

clippy_utils/src/sugg.rs

@@ -11,7 +11,6 @@ use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_hir::{Closure, ExprKind, HirId, MutTy, TyKind};
 use rustc_hir_typeck::expr_use_visitor::{Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{EarlyContext, LateContext, LintContext};
 use rustc_middle::hir::place::ProjectionKind;
 use rustc_middle::mir::{FakeReadCause, Mutability};
@@ -831,8 +830,9 @@ pub fn deref_closure_args(cx: &LateContext<'_>, closure: &hir::Expr<'_>) -> Opti
             applicability: Applicability::MachineApplicable,
         };
 
-        let infcx = cx.tcx.infer_ctxt().build();
-        ExprUseVisitor::new(&mut visitor, &infcx, def_id, cx.param_env, cx.typeck_results()).consume_body(closure_body);
+        ExprUseVisitor::for_clippy(cx, def_id, &mut visitor)
+            .consume_body(closure_body)
+            .into_ok();
 
         if !visitor.suggestion_start.is_empty() {
             return Some(DerefClosure {