diff --git a/libc/bionic/c32rtomb.cpp b/libc/bionic/c32rtomb.cpp
index 4fa76ff..a7cd207 100644
--- a/libc/bionic/c32rtomb.cpp
+++ b/libc/bionic/c32rtomb.cpp
@@ -78,7 +78,7 @@
     length = 4;
   } else {
     errno = EILSEQ;
-    return __MB_ERR_ILLEGAL_SEQUENCE;
+    return BIONIC_MULTIBYTE_RESULT_ILLEGAL_SEQUENCE;
   }
 
   // Output the octets representing the character in chunks