4 files changed, 9 insertions, 21 deletions
diff --git a/compiler/rustc_feature/src/removed.rs b/compiler/rustc_feature/src/removed.rs
index 4385e745bac..c0d3fc3fae0 100644
--- a/compiler/rustc_feature/src/removed.rs
+++ b/compiler/rustc_feature/src/removed.rs
@@ -158,6 +158,9 @@ declare_features! (
     /// Allows using `#[plugin_registrar]` on functions.
     (removed, plugin_registrar, "1.54.0", Some(29597), None,
      Some("plugins are no longer supported")),
+    /// Allows exhaustive integer pattern matching with `usize::MAX`/`isize::MIN`/`isize::MAX`.
+    (removed, precise_pointer_size_matching, "1.32.0", Some(56354), None,
+     Some("removed in favor of half-open ranges")),
     (removed, proc_macro_expr, "1.27.0", Some(54727), None,
      Some("subsumed by `#![feature(proc_macro_hygiene)]`")),
     (removed, proc_macro_gen, "1.27.0", Some(54727), None,
diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs
index dee68bff21d..1d4fa9c75d9 100644
--- a/compiler/rustc_feature/src/unstable.rs
+++ b/compiler/rustc_feature/src/unstable.rs
@@ -543,8 +543,6 @@ declare_features! (
     (unstable, offset_of_enum, "1.75.0", Some(106655), None),
     /// Allows using `#[optimize(X)]`.
     (unstable, optimize_attribute, "1.34.0", Some(54882), None),
-    /// Allows exhaustive integer pattern matching on `usize` and `isize`.
-    (unstable, precise_pointer_size_matching, "1.32.0", Some(56354), None),
     /// Allows macro attributes on expressions, statements and non-inline modules.
     (unstable, proc_macro_hygiene, "1.30.0", Some(54727), None),
     /// Allows `&raw const $place_expr` and `&raw mut $place_expr` expressions.
diff --git a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
index 80602713905..b72b9da21b7 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs
@@ -867,12 +867,6 @@ fn report_non_exhaustive_match<'p, 'tcx>(
                              exhaustively",
                     ));
                 }
-                if cx.tcx.sess.is_nightly_build() {
-                    err.help(format!(
-                            "add `#![feature(precise_pointer_size_matching)]` to the crate attributes to \
-                             enable precise `{ty}` matching",
-                        ));
-                }
             } else if ty == cx.tcx.types.str_ {
                 err.note("`&str` cannot be matched exhaustively, so a wildcard `_` is necessary");
             } else if cx.is_foreign_non_exhaustive_enum(ty) {
diff --git a/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs
index 31114190f07..ddcceeb7ef6 100644
--- a/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs
+++ b/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs
@@ -326,8 +326,7 @@ impl IntRange {
     /// `NegInfinity..PosInfinity`. In other words, as far as `IntRange` is concerned, there are
     /// values before `isize::MIN` and after `usize::MAX`/`isize::MAX`.
     /// This is to avoid e.g. `0..(u32::MAX as usize)` from being exhaustive on one architecture and
-    /// not others. See discussions around the `precise_pointer_size_matching` feature for more
-    /// details.
+    /// not others. This was decided in <https://github.com/rust-lang/rfcs/pull/2591>.
     ///
     /// These infinities affect splitting subtly: it is possible to get `NegInfinity..0` and
     /// `usize::MAX+1..PosInfinity` in the output. Diagnostics must be careful to handle these
@@ -380,7 +379,7 @@ impl IntRange {
     /// Whether the range denotes the fictitious values before `isize::MIN` or after
     /// `usize::MAX`/`isize::MAX` (see doc of [`IntRange::split`] for why these exist).
     pub(crate) fn is_beyond_boundaries<'tcx>(&self, ty: Ty<'tcx>, tcx: TyCtxt<'tcx>) -> bool {
-        ty.is_ptr_sized_integral() && !tcx.features().precise_pointer_size_matching && {
+        ty.is_ptr_sized_integral() && {
             // The two invalid ranges are `NegInfinity..isize::MIN` (represented as
             // `NegInfinity..0`), and `{u,i}size::MAX+1..PosInfinity`. `to_diagnostic_pat_range_bdy`
             // converts `MAX+1` to `PosInfinity`, and we couldn't have `PosInfinity` in `self.lo`
@@ -941,11 +940,8 @@ impl ConstructorSet {
                 }
             }
             &ty::Int(ity) => {
-                let range = if ty.is_ptr_sized_integral()
-                    && !cx.tcx.features().precise_pointer_size_matching
-                {
-                    // The min/max values of `isize` are not allowed to be observed unless the
-                    // `precise_pointer_size_matching` feature is enabled.
+                let range = if ty.is_ptr_sized_integral() {
+                    // The min/max values of `isize` are not allowed to be observed.
                     IntRange { lo: NegInfinity, hi: PosInfinity }
                 } else {
                     let bits = Integer::from_int_ty(&cx.tcx, ity).size().bits() as u128;
@@ -956,11 +952,8 @@ impl ConstructorSet {
                 Self::Integers { range_1: range, range_2: None }
             }
             &ty::Uint(uty) => {
-                let range = if ty.is_ptr_sized_integral()
-                    && !cx.tcx.features().precise_pointer_size_matching
-                {
-                    // The max value of `usize` is not allowed to be observed unless the
-                    // `precise_pointer_size_matching` feature is enabled.
+                let range = if ty.is_ptr_sized_integral() {
+                    // The max value of `usize` is not allowed to be observed.
                     let lo = MaybeInfiniteInt::new_finite(cx.tcx, ty, 0);
                     IntRange { lo, hi: PosInfinity }
                 } else {