diff --git a/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressSecLibRTSM/AArch64/GicV3.S b/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressSecLibRTSM/AArch64/GicV3.S
index 24ff2fc3d0..7d9c25c769 100644
--- a/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressSecLibRTSM/AArch64/GicV3.S
+++ b/ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressSecLibRTSM/AArch64/GicV3.S
@@ -13,6 +13,7 @@
 
 #include <AsmMacroIoLibV8.h>
 
+#ifndef __clang__
 // Register definitions used by GCC for GICv3 access.
 // These are defined by ARMCC, so keep them in the GCC specific code for now.
 #define ICC_SRE_EL2     S3_4_C12_C9_5
@@ -20,6 +21,7 @@
 #define ICC_CTLR_EL1    S3_0_C12_C12_4
 #define ICC_CTLR_EL3    S3_6_C12_C12_4
 #define ICC_PMR_EL1     S3_0_C4_C6_0
+#endif
 
 .text
 .align 3