diff --git a/linker/Android.bp b/linker/Android.bp
index 38a53f8..e103ade 100644
--- a/linker/Android.bp
+++ b/linker/Android.bp
@@ -176,6 +176,11 @@
         "-Wextra",
         "-Wunused",
         "-Werror",
+
+        // Define _USING_LIBCXX so <stdatomic.h> defers to the <atomic> header. When a Soong module
+        // uses the platform libc++, Soong automatically passes this macro, but the dynamic linker
+        // links against libc++ manually.
+        "-D_USING_LIBCXX",
     ],
 
     // TODO: split out the asflags.