From cf337d11191e50e472754a5cd4c1cd1fb6a648ca Mon Sep 17 00:00:00 2001
From: "Felix S. Klock II" <pnkfelix@pnkfx.org>
Date: Mon, 15 Mar 2021 16:39:41 -0400
Subject: [PATCH 1/3] Revert PR 81473 to resolve (on mainline) issues 81626 and
81658.
Revert "Add missing brace"
This reverts commit 85ad773049536d7fed9a94ae0ac74f97135c8655.
Revert "Simplify base_expr"
This reverts commit 899aae465eb4ef295dc1eeb2603f744568e0768c.
Revert "Warn write-only fields"
This reverts commit d3c69a4c0dd98af2611b7553d1a65afef6a6ccb0.
---
compiler/rustc_passes/src/dead.rs | 6 --
.../borrowck/borrowck-assign-to-subfield.rs | 1 -
.../ui/lint/dead-code/write-only-field.rs | 69 -------------------
.../ui/lint/dead-code/write-only-field.stderr | 44 ------------
4 files changed, 120 deletions(-)
delete mode 100644 src/test/ui/lint/dead-code/write-only-field.rs
delete mode 100644 src/test/ui/lint/dead-code/write-only-field.stderr
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
index 713d572b93a0b..f5b1e95aa1a33 100644
--- a/compiler/rustc_passes/src/dead.rs
+++ b/compiler/rustc_passes/src/dead.rs
@@ -338,12 +338,6 @@ impl<'tcx> Visitor<'tcx> for MarkSymbolVisitor<'tcx> {
hir::ExprKind::MethodCall(..) => {
self.lookup_and_handle_method(expr.hir_id);
}
- hir::ExprKind::Assign(ref left, ref right, ..) => {
- self.handle_assign(left);
- self.check_for_self_assign(expr);
- self.visit_expr(right);
- return;
- }
hir::ExprKind::Field(ref lhs, ..) => {
self.handle_field_access(&lhs, expr.hir_id);
}
diff --git a/src/test/ui/borrowck/borrowck-assign-to-subfield.rs b/src/test/ui/borrowck/borrowck-assign-to-subfield.rs
index dfa3a561ec7ee..050d702b625ab 100644
--- a/src/test/ui/borrowck/borrowck-assign-to-subfield.rs
+++ b/src/test/ui/borrowck/borrowck-assign-to-subfield.rs
@@ -1,6 +1,5 @@
// run-pass
// pretty-expanded FIXME #23616
-#![allow(dead_code)]
pub fn main() {
struct A {
diff --git a/src/test/ui/lint/dead-code/write-only-field.rs b/src/test/ui/lint/dead-code/write-only-field.rs
deleted file mode 100644
index 7b3f1e9f5b6cb..0000000000000
--- a/src/test/ui/lint/dead-code/write-only-field.rs
+++ /dev/null
@@ -1,69 +0,0 @@
-#![deny(dead_code)]
-
-struct S {
- f: i32, //~ ERROR: field is never read
- sub: Sub, //~ ERROR: field is never read
-}
-
-struct Sub {
- f: i32, //~ ERROR: field is never read
-}
-
-fn field_write(s: &mut S) {
- s.f = 1;
- s.sub.f = 2;
-}
-
-fn main() {
- let mut s = S { f: 0, sub: Sub { f: 0 } };
- field_write(&mut s);
-
- auto_deref();
- nested_boxes();
-}
-
-fn auto_deref() {
- struct E {
- x: bool,
- y: bool, //~ ERROR: field is never read
- }
-
- struct P<'a> {
- e: &'a mut E
- }
-
- impl P<'_> {
- fn f(&mut self) {
- self.e.x = true;
- self.e.y = true;
- }
- }
-
- let mut e = E { x: false, y: false };
- let mut p = P { e: &mut e };
- p.f();
- assert!(e.x);
-}
-
-fn nested_boxes() {
- struct A {
- b: Box<B>,
- }
-
- struct B {
- c: Box<C>,
- }
-
- struct C {
- u: u32, //~ ERROR: field is never read
- v: u32, //~ ERROR: field is never read
- }
-
- let mut a = A {
- b: Box::new(B {
- c: Box::new(C { u: 0, v: 0 }),
- }),
- };
- a.b.c.v = 10;
- a.b.c = Box::new(C { u: 1, v: 2 });
-}
diff --git a/src/test/ui/lint/dead-code/write-only-field.stderr b/src/test/ui/lint/dead-code/write-only-field.stderr
deleted file mode 100644
index a191d22c8b94c..0000000000000
--- a/src/test/ui/lint/dead-code/write-only-field.stderr
+++ /dev/null
@@ -1,44 +0,0 @@
-error: field is never read: `f`
- --> $DIR/write-only-field.rs:4:5
- |
-LL | f: i32,
- | ^^^^^^
- |
-note: the lint level is defined here
- --> $DIR/write-only-field.rs:1:9
- |
-LL | #![deny(dead_code)]
- | ^^^^^^^^^
-
-error: field is never read: `sub`
- --> $DIR/write-only-field.rs:5:5
- |
-LL | sub: Sub,
- | ^^^^^^^^
-
-error: field is never read: `f`
- --> $DIR/write-only-field.rs:9:5
- |
-LL | f: i32,
- | ^^^^^^
-
-error: field is never read: `y`
- --> $DIR/write-only-field.rs:28:9
- |
-LL | y: bool,
- | ^^^^^^^
-
-error: field is never read: `u`
- --> $DIR/write-only-field.rs:58:9
- |
-LL | u: u32,
- | ^^^^^^
-
-error: field is never read: `v`
- --> $DIR/write-only-field.rs:59:9
- |
-LL | v: u32,
- | ^^^^^^
-
-error: aborting due to 6 previous errors
-
From b6e9d069eb950226c8c75d2b516d8575eb6cf54e Mon Sep 17 00:00:00 2001
From: "Felix S. Klock II" <pnkfelix@pnkfx.org>
Date: Wed, 21 Jul 2021 22:57:10 -0400
Subject: [PATCH 2/3] Allow some temporarily dead code.
I expect these two methods to come back very soon; noise of removing them to satisfy lint seems wrong.
---
compiler/rustc_passes/src/dead.rs | 2 ++
1 file changed, 2 insertions(+)
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
index f5b1e95aa1a33..b71ec700f81c8 100644
--- a/compiler/rustc_passes/src/dead.rs
+++ b/compiler/rustc_passes/src/dead.rs
@@ -134,6 +134,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
}
}
+ #[allow(dead_code)] // FIXME(81658): should be used + lint reinstated after #83171 relands.
fn handle_assign(&mut self, expr: &'tcx hir::Expr<'tcx>) {
if self
.typeck_results()
@@ -150,6 +151,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
}
}
+ #[allow(dead_code)] // FIXME(81658): should be used + lint reinstated after #83171 relands.
fn check_for_self_assign(&mut self, assign: &'tcx hir::Expr<'tcx>) {
fn check_for_self_assign_helper(
tcx: TyCtxt<'tcx>,
From ee2bb1f33868414f7cca441c6be3aec8d6a1d81a Mon Sep 17 00:00:00 2001
From: "Felix S. Klock II" <pnkfelix@pnkfx.org>
Date: Wed, 21 Jul 2021 23:03:06 -0400
Subject: [PATCH 3/3] temporarily ignore a test until we reland PR 83171.
---
src/test/ui/lint/dead-code/self-assign.rs | 2 ++
1 file changed, 2 insertions(+)
diff --git a/src/test/ui/lint/dead-code/self-assign.rs b/src/test/ui/lint/dead-code/self-assign.rs
index b8bf7d860c415..ea7ce98d88413 100644
--- a/src/test/ui/lint/dead-code/self-assign.rs
+++ b/src/test/ui/lint/dead-code/self-assign.rs
@@ -1,6 +1,8 @@
// Test that dead code warnings are issued for superfluous assignments of
// fields or variables to themselves (issue #75356).
+// ignore-test FIXME(81658, 83171)
+
// check-pass
#![allow(unused_assignments)]
#![warn(dead_code)]