diff --git a/libc/arch-arm/bionic/atomics_arm.S b/libc/arch-arm/bionic/atomics_arm.S
index 047541f..f2e369d 100644
--- a/libc/arch-arm/bionic/atomics_arm.S
+++ b/libc/arch-arm/bionic/atomics_arm.S
@@ -142,7 +142,7 @@
 /* r0(new) r1(addr) -> r0(old) */
 /* replaced swp instruction with ldrex/strex for ARMv6 & ARMv7 */
 __atomic_swap:
-#if defined (_ARM_HAVE_LDREX_STREX)
+#if defined (__ARM_HAVE_LDREX_STREX)
 1:  ldrex   r2, [r1]
     strex   r3, r0, [r1]
     teq     r3, #0
diff --git a/libc/arch-arm/include/machine/cpu-features.h b/libc/arch-arm/include/machine/cpu-features.h
index ecf6ff6..5af325b 100644
--- a/libc/arch-arm/include/machine/cpu-features.h
+++ b/libc/arch-arm/include/machine/cpu-features.h
@@ -149,11 +149,11 @@
 #  define __ARM_HAVE_PC_INTERWORK
 #endif
 
-/* define _ARM_HAVE_LDREX_STREX for ARMv6 and ARMv7 architecure to be
+/* define __ARM_HAVE_LDREX_STREX for ARMv6 and ARMv7 architecure to be
  * used in replacement of depricated swp instruction
  */
 #if __ARM_ARCH__ >= 6
-#  define _ARM_HAVE_LDREX_STREX
+#  define __ARM_HAVE_LDREX_STREX
 #endif