types/dynamicpb: switch atomicExtFiles to atomic.Uint64 type
(Go Protobuf currently requires Go 1.21.)
This guarantees correct alignment on stack-allocated values, too.
Change-Id: If713532c20326a7ee3f1dd5c77f49c1d52f6eb9a
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/641017
Reviewed-by: Chressie Himpel <chressie@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/types/dynamicpb/types.go b/types/dynamicpb/types.go
index c432817..8e759fc 100644
--- a/types/dynamicpb/types.go
+++ b/types/dynamicpb/types.go
@@ -28,11 +28,7 @@
type Types struct {
// atomicExtFiles is used with sync/atomic and hence must be the first word
// of the struct to guarantee 64-bit alignment.
- //
- // TODO(stapelberg): once we only support Go 1.19 and newer, switch this
- // field to be of type atomic.Uint64 to guarantee alignment on
- // stack-allocated values, too.
- atomicExtFiles uint64
+ atomicExtFiles atomic.Uint64
extMu sync.Mutex
files *protoregistry.Files
@@ -90,7 +86,7 @@
func (t *Types) FindExtensionByNumber(message protoreflect.FullName, field protoreflect.FieldNumber) (protoreflect.ExtensionType, error) {
// Construct the extension number map lazily, since not every user will need it.
// Update the map if new files are added to the registry.
- if atomic.LoadUint64(&t.atomicExtFiles) != uint64(t.files.NumFiles()) {
+ if t.atomicExtFiles.Load() != uint64(t.files.NumFiles()) {
t.updateExtensions()
}
xd := t.extensionsByMessage[extField{message, field}]
@@ -133,10 +129,10 @@
func (t *Types) updateExtensions() {
t.extMu.Lock()
defer t.extMu.Unlock()
- if atomic.LoadUint64(&t.atomicExtFiles) == uint64(t.files.NumFiles()) {
+ if t.atomicExtFiles.Load() == uint64(t.files.NumFiles()) {
return
}
- defer atomic.StoreUint64(&t.atomicExtFiles, uint64(t.files.NumFiles()))
+ defer t.atomicExtFiles.Store(uint64(t.files.NumFiles()))
t.files.RangeFiles(func(fd protoreflect.FileDescriptor) bool {
t.registerExtensions(fd.Extensions())
t.registerExtensionsInMessages(fd.Messages())
