diff --git a/go/analysis/passes/copylock/copylock_test.go b/go/analysis/passes/copylock/copylock_test.go
index c22001ca3ea..7667f35b4b3 100644
--- a/go/analysis/passes/copylock/copylock_test.go
+++ b/go/analysis/passes/copylock/copylock_test.go
@@ -16,6 +16,10 @@ import (
 
 func Test(t *testing.T) {
 	testdata := analysistest.TestData()
+	// TODO(mknyszek): Add "unfortunate" package once CL 627777 lands. That CL changes
+	// the internals of the sync package structures to carry an explicit noCopy to prevent
+	// problems from changes to the implementations of those structures, such as these
+	// tests failing, or a bad user experience.
 	analysistest.Run(t, testdata, copylock.Analyzer, "a", "typeparams", "issue67787")
 }
 
diff --git a/go/analysis/passes/copylock/testdata/src/a/copylock_func.go b/go/analysis/passes/copylock/testdata/src/a/copylock_func.go
index 0d3168f1ef1..c27862627b9 100644
--- a/go/analysis/passes/copylock/testdata/src/a/copylock_func.go
+++ b/go/analysis/passes/copylock/testdata/src/a/copylock_func.go
@@ -5,20 +5,25 @@
 // This file contains tests for the copylock checker's
 // function declaration analysis.
 
+// There are two cases missing from this file which
+// are located in the "unfortunate" package in the
+// testdata directory. Once the go.mod >= 1.26 for this
+// repository, merge local_go124.go back into this file.
+
 package a
 
 import "sync"
 
 func OkFunc(*sync.Mutex) {}
 func BadFunc(sync.Mutex) {} // want "BadFunc passes lock by value: sync.Mutex"
-func BadFunc2(sync.Map)  {} // want "BadFunc2 passes lock by value: sync.Map contains sync.Mutex"
+func BadFunc2(sync.Map)  {} // want "BadFunc2 passes lock by value: sync.Map contains sync.(Mutex|noCopy)"
 func OkRet() *sync.Mutex {}
 func BadRet() sync.Mutex {} // Don't warn about results
 
 var (
 	OkClosure   = func(*sync.Mutex) {}
 	BadClosure  = func(sync.Mutex) {} // want "func passes lock by value: sync.Mutex"
-	BadClosure2 = func(sync.Map) {}   // want "func passes lock by value: sync.Map contains sync.Mutex"
+	BadClosure2 = func(sync.Map) {}   // want "func passes lock by value: sync.Map contains sync.(Mutex|noCopy)"
 )
 
 type EmbeddedRWMutex struct {
@@ -118,19 +123,3 @@ func AcceptedCases() {
 	x = BadRet()           // function call on RHS is OK (#16227)
 	x = *OKRet()           // indirection of function call on RHS is OK (#16227)
 }
-
-// TODO: Unfortunate cases
-
-// Non-ideal error message:
-// Since we're looking for Lock methods, sync.Once's underlying
-// sync.Mutex gets called out, but without any reference to the sync.Once.
-type LocalOnce sync.Once
-
-func (LocalOnce) Bad() {} // want `Bad passes lock by value: a.LocalOnce contains sync.\b.*`
-
-// False negative:
-// LocalMutex doesn't have a Lock method.
-// Nevertheless, it is probably a bad idea to pass it by value.
-type LocalMutex sync.Mutex
-
-func (LocalMutex) Bad() {} // WANTED: An error here :(
diff --git a/go/analysis/passes/copylock/testdata/src/unfortunate/local_go123.go b/go/analysis/passes/copylock/testdata/src/unfortunate/local_go123.go
new file mode 100644
index 00000000000..1aa3abc788d
--- /dev/null
+++ b/go/analysis/passes/copylock/testdata/src/unfortunate/local_go123.go
@@ -0,0 +1,25 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !go1.24
+
+package unfortunate
+
+import "sync"
+
+// TODO: Unfortunate cases
+
+// Non-ideal error message:
+// Since we're looking for Lock methods, sync.Once's underlying
+// sync.Mutex gets called out, but without any reference to the sync.Once.
+type LocalOnce sync.Once
+
+func (LocalOnce) Bad() {} // want `Bad passes lock by value: a.LocalOnce contains sync.\b.*`
+
+// False negative:
+// LocalMutex doesn't have a Lock method.
+// Nevertheless, it is probably a bad idea to pass it by value.
+type LocalMutex sync.Mutex
+
+func (LocalMutex) Bad() {} // WANTED: An error here :(
diff --git a/go/analysis/passes/copylock/testdata/src/unfortunate/local_go124.go b/go/analysis/passes/copylock/testdata/src/unfortunate/local_go124.go
new file mode 100644
index 00000000000..505b105a9b1
--- /dev/null
+++ b/go/analysis/passes/copylock/testdata/src/unfortunate/local_go124.go
@@ -0,0 +1,19 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.24
+
+package unfortunate
+
+import "sync"
+
+// Cases where the interior sync.noCopy shows through.
+
+type LocalOnce sync.Once
+
+func (LocalOnce) Bad() {} // want "Bad passes lock by value: a.LocalOnce contains sync.noCopy"
+
+type LocalMutex sync.Mutex
+
+func (LocalMutex) Bad() {} // want "Bad passes lock by value: a.LocalMutex contains sync.noCopy"