From 7553f464308db4d5508e81dd4d4ad92252186a68 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9my=20Rakic?= <remy.rakic+github@gmail.com>
Date: Thu, 4 Dec 2025 10:41:13 +0000
Subject: [PATCH 1/3] inline constant typeck constraint

---
 .../src/polonius/typeck_constraints.rs        | 32 +++++++------------
 1 file changed, 12 insertions(+), 20 deletions(-)

diff --git a/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs b/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs
index e4e52962bf7f9..7d406837f5ae3 100644
--- a/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs
+++ b/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs
@@ -45,7 +45,6 @@ pub(super) fn convert_typeck_constraints<'tcx>(
                 {
                     localize_statement_constraint(
                         tcx,
-                        body,
                         stmt,
                         &outlives_constraint,
                         point,
@@ -74,7 +73,6 @@ pub(super) fn convert_typeck_constraints<'tcx>(
 /// needed CFG `from`-`to` intra-block nodes.
 fn localize_statement_constraint<'tcx>(
     tcx: TyCtxt<'tcx>,
-    body: &Body<'tcx>,
     stmt: &Statement<'tcx>,
     outlives_constraint: &OutlivesConstraint<'tcx>,
     current_point: PointIndex,
@@ -114,28 +112,22 @@ fn localize_statement_constraint<'tcx>(
                 },
                 "there should be no common regions between the LHS and RHS of an assignment"
             );
-
-            let lhs_ty = body.local_decls[lhs.local].ty;
-            let successor_point = current_point;
-            compute_constraint_direction(
-                tcx,
-                outlives_constraint,
-                &lhs_ty,
-                current_point,
-                successor_point,
-                universal_regions,
-            )
         }
         _ => {
-            // For the other cases, we localize an outlives constraint to where it arises.
-            LocalizedOutlivesConstraint {
-                source: outlives_constraint.sup,
-                from: current_point,
-                target: outlives_constraint.sub,
-                to: current_point,
-            }
+            // Assignments should be the only statement that can both generate constraints that
+            // apply on entry (specific to the RHS place) *and* others that only apply on exit (the
+            // subset of RHS regions that actually flow into the LHS): i.e., where midpoints would
+            // be used to ensure the former happen before the latter, within the same MIR Location.
         }
     }
+
+    // We generally localize an outlives constraint to where it arises.
+    LocalizedOutlivesConstraint {
+        source: outlives_constraint.sup,
+        from: current_point,
+        target: outlives_constraint.sub,
+        to: current_point,
+    }
 }
 
 /// For a given outlives constraint arising from a MIR terminator, localize the constraint with the

From 38f795dd028fd02b28278c43a828907e34f82cbe Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?R=C3=A9my=20Rakic?= <remy.rakic+github@gmail.com>
Date: Thu, 4 Dec 2025 11:18:06 +0000
Subject: [PATCH 2/3] update comments

---
 .../rustc_borrowck/src/polonius/typeck_constraints.rs     | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs b/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs
index 7d406837f5ae3..cfe9376fb5029 100644
--- a/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs
+++ b/compiler/rustc_borrowck/src/polonius/typeck_constraints.rs
@@ -142,14 +142,12 @@ fn localize_terminator_constraint<'tcx>(
     universal_regions: &UniversalRegions<'tcx>,
 ) -> LocalizedOutlivesConstraint {
     // FIXME: check if other terminators need the same handling as `Call`s, in particular
-    // Assert/Yield/Drop. A handful of tests are failing with Drop related issues, as well as some
-    // coroutine tests, and that may be why.
+    // Assert/Yield/Drop.
     match &terminator.kind {
         // FIXME: also handle diverging calls.
         TerminatorKind::Call { destination, target: Some(target), .. } => {
-            // Calls are similar to assignments, and thus follow the same pattern. If there is a
-            // target for the call we also relate what flows into the destination here to entry to
-            // that successor.
+            // If there is a target for the call we also relate what flows into the destination here
+            // to entry to that successor.
             let destination_ty = destination.ty(&body.local_decls, tcx);
             let successor_location = Location { block: *target, statement_index: 0 };
             let successor_point = liveness.point_from_location(successor_location);

From ac533e25dbcbb59ffc8f92b1034b9258047c6986 Mon Sep 17 00:00:00 2001
From: Manuel Drehwald <git@manuel.drehwald.info>
Date: Thu, 22 Jan 2026 20:01:05 -0800
Subject: [PATCH 3/3] update enzyme, includes an extra patch to fix MacOS
 builds in CI

---
 src/tools/enzyme | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/tools/enzyme b/src/tools/enzyme
index 09f4820b78e2d..eb72baf793a83 160000
--- a/src/tools/enzyme
+++ b/src/tools/enzyme
@@ -1 +1 @@
-Subproject commit 09f4820b78e2d71b85a3278bbb41dc3a012e84dd
+Subproject commit eb72baf793a8385acb7dce614c81ba45c5be20fb