diff --git a/dl/sp/api/armSP.h b/dl/sp/api/armSP.h
index 8f804ac..df504ea 100644
--- a/dl/sp/api/armSP.h
+++ b/dl/sp/api/armSP.h
@@ -95,7 +95,7 @@
  */
 static inline long fastlog2(long x) {
   long out;
-  asm("clz %0,%1\n\t"
+  __asm__ ("clz %0,%1\n\t"
       "sub %0, %0, #63\n\t"
       "neg %0, %0\n\t"
       : "=r"(out)