diff --git a/gcm.cpp b/gcm.cpp
index 3759a175..d1b57b5f 100644
--- a/gcm.cpp
+++ b/gcm.cpp
@@ -14,7 +14,7 @@
 
 // Clang 3.3 integrated assembler crash on Linux. Other versions produce incorrect results.
 //   Clang has never handled Intel ASM very well. I wish LLVM would fix it.
-#if defined(__clang__)
+#if defined(CRYPTOPP_DISABLE_INTEL_ASM)
 # undef CRYPTOPP_X86_ASM_AVAILABLE
 # undef CRYPTOPP_X32_ASM_AVAILABLE
 # undef CRYPTOPP_X64_ASM_AVAILABLE