diff --git a/nsprpub/pr/include/md/_darwin.h b/nsprpub/pr/include/md/_darwin.h
index 1d79d3d82d..c6340ce2d5 100644
--- a/nsprpub/pr/include/md/_darwin.h
+++ b/nsprpub/pr/include/md/_darwin.h
@@ -40,7 +40,7 @@
 
 #undef  HAVE_STACK_GROWING_UP
 #define HAVE_DLL
-#if defined(__x86_64__) || TARGET_OS_IPHONE
+#if defined(__x86_64__) || defined(__aarch64__)
 #define USE_DLFCN
 #else
 #define USE_MACH_DYLD