Remove suggestion to use atomics

estebank · estebank · commit f7ddba088fa3 · 2025-08-22T22:32:29.000Z
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -6,7 +6,6 @@ use core::ops::ControlFlow;
 use either::Either;
 use hir::{ExprKind, Param};
 use rustc_abi::FieldIdx;
-use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{Applicability, Diag};
 use rustc_hir::intravisit::Visitor;
 use rustc_hir::{self as hir, BindingMode, ByRef, Node};
@@ -952,8 +951,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         }
     }
 
-    /// When modifying a binding from inside of an `Fn` closure, point at the binding definition
-    /// and suggest using an `std::sync` type that would allow the code to compile.
+    /// When modifying a binding from inside of an `Fn` closure, point at the binding definition.
     fn point_at_binding_outside_closure(
         &self,
         err: &mut Diag<'_>,
@@ -985,31 +983,6 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                             && let hir::def::Res::Local(hir_id) = path.res
                             && let hir::Node::Pat(pat) = self.infcx.tcx.hir_node(hir_id)
                         {
-                            let hir = self.infcx.tcx.hir();
-                            let def_id = hir.enclosing_body_owner(self.mir_hir_id());
-                            let typeck_results = self.infcx.tcx.typeck(def_id);
-                            let ty = typeck_results.node_type_opt(expr.hir_id);
-                            if let Some(ty) = ty {
-                                let mutex = format!("std::sync::atomic::Mutex<{ty}>");
-                                let mutex = mutex.as_str();
-                                let suggestions: FxHashMap<_, _> = [
-                                    (self.infcx.tcx.types.isize, "std::sync::atomic::AtomicIsize"),
-                                    (self.infcx.tcx.types.usize, "std::sync::atomic::AtomicUsize"),
-                                    (self.infcx.tcx.types.i64, "std::sync::atomic::AtomicI64"),
-                                    (self.infcx.tcx.types.u64, "std::sync::atomic::AtomicU64"),
-                                    (self.infcx.tcx.types.i32, "std::sync::atomic::AtomicI32"),
-                                    (self.infcx.tcx.types.u32, "std::sync::atomic::AtomicU32"),
-                                    (self.infcx.tcx.types.i16, "std::sync::atomic::AtomicI16"),
-                                    (self.infcx.tcx.types.u16, "std::sync::atomic::AtomicU16"),
-                                    (self.infcx.tcx.types.i8, "std::sync::atomic::AtomicI8"),
-                                    (self.infcx.tcx.types.u8, "std::sync::atomic::AtomicU8"),
-                                    (self.infcx.tcx.types.bool, "std::sync::atomic::AtomicBool"),
-                                ]
-                                .into_iter()
-                                .collect();
-                                let ty = suggestions.get(&ty).unwrap_or(&mutex);
-                                err.help(format!("consider using `{ty}` instead, which allows for multiple threads to access and modify the value"));
-                            }
                             let name = upvar.to_string(self.infcx.tcx);
                             err.span_label(
                                 pat.span,
diff --git a/tests/ui/async-await/async-closures/wrong-fn-kind.stderr b/tests/ui/async-await/async-closures/wrong-fn-kind.stderr
@@ -36,8 +36,6 @@ LL |     needs_async_fn(async || {
 LL |
 LL |         x += 1;
    |         - mutable borrow occurs due to use of `x` in closure
-   |
-   = help: consider using `std::sync::atomic::AtomicI32` instead, which allows for multiple threads to access and modify the value
 
 error: aborting due to 2 previous errors
 
diff --git a/tests/ui/borrowck/borrow-immutable-upvar-mutation.stderr b/tests/ui/borrowck/borrow-immutable-upvar-mutation.stderr
@@ -11,8 +11,6 @@ LL |         let _f = to_fn(|| x = 42);
    |                  |     |
    |                  |     in this closure
    |                  expects `Fn` instead of `FnMut`
-   |
-   = help: consider using `std::sync::atomic::AtomicI32` instead, which allows for multiple threads to access and modify the value
 
 error[E0596]: cannot borrow `y` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:24:31
@@ -27,8 +25,6 @@ LL |         let _g = to_fn(|| set(&mut y));
    |                  |     |
    |                  |     in this closure
    |                  expects `Fn` instead of `FnMut`
-   |
-   = help: consider using `std::sync::atomic::AtomicUsize` instead, which allows for multiple threads to access and modify the value
 
 error[E0594]: cannot assign to `z`, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:29:22
@@ -44,8 +40,6 @@ LL |             to_fn(|| z = 42);
    |             |     |
    |             |     in this closure
    |             expects `Fn` instead of `FnMut`
-   |
-   = help: consider using `std::sync::atomic::AtomicUsize` instead, which allows for multiple threads to access and modify the value
 
 error[E0594]: cannot assign to `x`, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-immutable-upvar-mutation.rs:36:32
diff --git a/tests/ui/borrowck/borrow-raw-address-of-mutability.stderr b/tests/ui/borrowck/borrow-raw-address-of-mutability.stderr
@@ -48,8 +48,6 @@ LL |     let f = make_fn(|| {
    |             expects `Fn` instead of `FnMut`
 LL |         let y = &raw mut x;
    |                 ^^^^^^^^^^ cannot borrow as mutable
-   |
-   = help: consider using `std::sync::atomic::AtomicI32` instead, which allows for multiple threads to access and modify the value
 
 error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/borrow-raw-address-of-mutability.rs:35:17
diff --git a/tests/ui/borrowck/mutability-errors.stderr b/tests/ui/borrowck/mutability-errors.stderr
@@ -148,8 +148,6 @@ LL |     fn_ref(|| {
    |     expects `Fn` instead of `FnMut`
 LL |         x = (1,);
    |         ^^^^^^^^ cannot assign
-   |
-   = help: consider using `std::sync::atomic::Mutex<(i32,)>` instead, which allows for multiple threads to access and modify the value
 
 error[E0594]: cannot assign to `x.0`, as `Fn` closures cannot mutate their captured variables
   --> $DIR/mutability-errors.rs:41:9
@@ -166,8 +164,6 @@ LL |     fn_ref(|| {
 LL |         x = (1,);
 LL |         x.0 = 1;
    |         ^^^^^^^ cannot assign
-   |
-   = help: consider using `std::sync::atomic::Mutex<(i32,)>` instead, which allows for multiple threads to access and modify the value
 
 error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/mutability-errors.rs:42:9
@@ -184,8 +180,6 @@ LL |     fn_ref(|| {
 ...
 LL |         &mut x;
    |         ^^^^^^ cannot borrow as mutable
-   |
-   = help: consider using `std::sync::atomic::Mutex<(i32,)>` instead, which allows for multiple threads to access and modify the value
 
 error[E0596]: cannot borrow `x.0` as mutable, as `Fn` closures cannot mutate their captured variables
   --> $DIR/mutability-errors.rs:43:9
@@ -202,8 +196,6 @@ LL |     fn_ref(|| {
 ...
 LL |         &mut x.0;
    |         ^^^^^^^^ cannot borrow as mutable
-   |
-   = help: consider using `std::sync::atomic::Mutex<(i32,)>` instead, which allows for multiple threads to access and modify the value
 
 error[E0594]: cannot assign to `x`, as it is a captured variable in a `Fn` closure
   --> $DIR/mutability-errors.rs:46:9
diff --git a/tests/ui/closures/aliasability-violation-with-closure-21600.stderr b/tests/ui/closures/aliasability-violation-with-closure-21600.stderr
@@ -12,8 +12,6 @@ LL |         call_it(|| x.gen_mut());
    |         |       |
    |         |       in this closure
    |         expects `Fn` instead of `FnMut`
-   |
-   = help: consider using `std::sync::atomic::Mutex<A>` instead, which allows for multiple threads to access and modify the value
 
 error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/aliasability-violation-with-closure-21600.rs:15:17
@@ -32,8 +30,6 @@ LL |         call_it(|| x.gen_mut());
    |                 ^^ - mutable borrow occurs due to use of `x` in closure
    |                 |
    |                 cannot borrow as mutable
-   |
-   = help: consider using `std::sync::atomic::Mutex<A>` instead, which allows for multiple threads to access and modify the value
 
 error: aborting due to 2 previous errors
 
diff --git a/tests/ui/closures/wrong-closure-arg-suggestion-125325.stderr b/tests/ui/closures/wrong-closure-arg-suggestion-125325.stderr
@@ -12,8 +12,6 @@ LL |     s.assoc_func(|| x = ());
    |       |          |  cannot assign
    |       |          in this closure
    |       expects `Fn` instead of `FnMut`
-   |
-   = help: consider using `std::sync::atomic::Mutex<()>` instead, which allows for multiple threads to access and modify the value
 
 error[E0594]: cannot assign to `x`, as it is a captured variable in a `Fn` closure
   --> $DIR/wrong-closure-arg-suggestion-125325.rs:25:13
@@ -29,8 +27,6 @@ LL |     func(|| x = ())
    |     |    |
    |     |    in this closure
    |     expects `Fn` instead of `FnMut`
-   |
-   = help: consider using `std::sync::atomic::Mutex<()>` instead, which allows for multiple threads to access and modify the value
 
 error: aborting due to 2 previous errors
 
diff --git a/tests/ui/nll/closure-captures.stderr b/tests/ui/nll/closure-captures.stderr
@@ -58,8 +58,6 @@ LL |         ||
    |         ^^ cannot borrow as mutable
 LL |          x = 1;}
    |          - mutable borrow occurs due to use of `x` in closure
-   |
-   = help: consider using `std::sync::atomic::AtomicI32` instead, which allows for multiple threads to access and modify the value
 
 error[E0596]: cannot borrow `x` as mutable, as it is a captured variable in a `Fn` closure
   --> $DIR/closure-captures.rs:31:9
@@ -103,8 +101,6 @@ LL |         ||
    |         ^^ cannot borrow as mutable
 LL |          x = 1;}
    |          - mutable borrow occurs due to use of `x` in closure
-   |
-   = help: consider using `std::sync::atomic::AtomicI32` instead, which allows for multiple threads to access and modify the value
 
 error[E0594]: cannot assign to `x`, as it is not declared as mutable
   --> $DIR/closure-captures.rs:43:5
diff --git a/tests/ui/unboxed-closures/unboxed-closures-mutated-upvar-from-fn-closure.stderr b/tests/ui/unboxed-closures/unboxed-closures-mutated-upvar-from-fn-closure.stderr
@@ -12,8 +12,6 @@ LL |     call(|| {
    |     expects `Fn` instead of `FnMut`
 LL |         counter += 1;
    |         ^^^^^^^^^^^^ cannot assign
-   |
-   = help: consider using `std::sync::atomic::AtomicI32` instead, which allows for multiple threads to access and modify the value
 
 error: aborting due to 1 previous error
 
