diff --git a/libc/malloc_debug/DebugData.cpp b/libc/malloc_debug/DebugData.cpp
index e9974d7..d6ca998 100644
--- a/libc/malloc_debug/DebugData.cpp
+++ b/libc/malloc_debug/DebugData.cpp
@@ -47,7 +47,7 @@
     need_header_ = true;
 
     // Initialize all of the static header offsets.
-    pointer_offset_ = BIONIC_ALIGN(sizeof(Header), MINIMUM_ALIGNMENT_BYTES);
+    pointer_offset_ = __BIONIC_ALIGN(sizeof(Header), MINIMUM_ALIGNMENT_BYTES);
 
     if (config_.options() & BACKTRACE) {
       backtrace.reset(new BacktraceData(this, config_, &pointer_offset_));