diff --git a/libc/malloc_debug/Config.cpp b/libc/malloc_debug/Config.cpp
index e3798ab..3cecf9b 100644
--- a/libc/malloc_debug/Config.cpp
+++ b/libc/malloc_debug/Config.cpp
@@ -191,7 +191,7 @@
 
   // It's necessary to align the front guard to MINIMUM_ALIGNMENT_BYTES to
   // make sure that the header is aligned properly.
-  front_guard_bytes_ = BIONIC_ALIGN(rear_guard_bytes_, MINIMUM_ALIGNMENT_BYTES);
+  front_guard_bytes_ = __BIONIC_ALIGN(rear_guard_bytes_, MINIMUM_ALIGNMENT_BYTES);
   return true;
 }
 
@@ -201,7 +201,7 @@
   }
   // It's necessary to align the front guard to MINIMUM_ALIGNMENT_BYTES to
   // make sure that the header is aligned properly.
-  front_guard_bytes_ = BIONIC_ALIGN(front_guard_bytes_, MINIMUM_ALIGNMENT_BYTES);
+  front_guard_bytes_ = __BIONIC_ALIGN(front_guard_bytes_, MINIMUM_ALIGNMENT_BYTES);
   return true;
 }