diff --git a/include/intrin.hpp b/include/intrin.hpp
index 6a9b9412..b4ce875a 100644
--- a/include/intrin.hpp
+++ b/include/intrin.hpp
@@ -19,28 +19,36 @@ namespace FXSR
 {
     void _fxsave(void *mem_addr)
     {
+#ifdef a64
         __builtin_ia32_fxsave(mem_addr);
+#endif
     }
 
     void _fxrstor(void *mem_addr)
     {
+#ifdef a64
         __builtin_ia32_fxrstor(mem_addr);
+#endif
     }
 
     void _fxsave64(void *mem_addr)
     {
+#ifdef a64
         asmv("fxsaveq (%0)"
              :
              : "r"(mem_addr)
              : "memory");
+#endif
     }
 
     void _fxrstor64(void *mem_addr)
     {
+#ifdef a64
         asmv("fxrstorq (%0)"
              :
              : "r"(mem_addr)
              : "memory");
+#endif
     }
 }