diff --git a/edk/Cper.h b/edk/Cper.h
index a2e2fb6..536858f 100644
--- a/edk/Cper.h
+++ b/edk/Cper.h
@@ -1266,6 +1266,7 @@
 extern EFI_GUID   gEfiDirectedIoDMArErrorSectionGuid;
 extern EFI_GUID   gEfiIommuDMArErrorSectionGuid;
 extern EFI_GUID   gEfiCcixPerLogErrorSectionGuid;
+extern EFI_GUID   gEfiCxlProtocolErrorSectionGuid;
 #pragma pack()
 
 #if defined (MDE_CPU_IA32) || defined (MDE_CPU_X64)