diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 0fd17d1..981c60d 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -52,6 +52,7 @@
 #include "DisplayDevice.h"
 #include "DisplayHardware/HWC2.h"
 #include "DisplayHardware/PowerAdvisor.h"
+#include "DisplayIdGenerator.h"
 #include "Effects/Daltonizer.h"
 #include "FrameTracker.h"
 #include "LayerVector.h"
@@ -945,8 +946,8 @@
         return it != mPhysicalDisplayTokens.end() ? it->second : nullptr;
     }
 
-    std::optional<DisplayId> getPhysicalDisplayIdLocked(const sp<IBinder>& displayToken) const
-            REQUIRES(mStateLock) {
+    std::optional<PhysicalDisplayId> getPhysicalDisplayIdLocked(
+            const sp<IBinder>& displayToken) const REQUIRES(mStateLock) {
         for (const auto& [id, token] : mPhysicalDisplayTokens) {
             if (token == displayToken) {
                 return id;
@@ -1109,6 +1110,8 @@
     std::unordered_map<PhysicalDisplayId, sp<IBinder>> mPhysicalDisplayTokens
             GUARDED_BY(mStateLock);
 
+    RandomDisplayIdGenerator<GpuVirtualDisplayId> mGpuVirtualDisplayIdGenerator;
+
     std::unordered_map<BBinder*, wp<Layer>> mLayersByLocalBinderToken GUARDED_BY(mStateLock);
 
     // don't use a lock for these, we don't care