diff --git a/llvm/lib/Target/AArch64/AArch64Subtarget.h b/llvm/lib/Target/AArch64/AArch64Subtarget.h
index 96ef9357a121e..904f0b9f50544 100644
--- a/llvm/lib/Target/AArch64/AArch64Subtarget.h
+++ b/llvm/lib/Target/AArch64/AArch64Subtarget.h
@@ -300,6 +300,13 @@ class AArch64Subtarget final : public AArch64GenSubtargetInfo {
   unsigned classifyGlobalFunctionReference(const GlobalValue *GV,
                                            const TargetMachine &TM) const;
 
+  /// This function is design to compatible with the function def in other
+  /// targets and escape build error about the virtual function def in base
+  /// class TargetSubtargetInfo. Updeate me if AArch64 target need to use it.
+  unsigned char classifyGlobalFunctionReference(const GlobalValue *GV) const {
+    return 0;
+  }
+
   void overrideSchedPolicy(MachineSchedPolicy &Policy,
                            unsigned NumRegionInstrs) const override;