diff --git a/libc/include/wchar.h b/libc/include/wchar.h
index fe2fe07..4ac468d 100644
--- a/libc/include/wchar.h
+++ b/libc/include/wchar.h
@@ -41,11 +41,9 @@
 
 typedef __WINT_TYPE__  wint_t;
 typedef struct {
-#ifdef __LP32__
-  int dummy;
-#else
-  // 8 bytes should be enough to support at least UTF-8
-  char __reserved[8];
+  uint8_t __seq[4];
+#ifdef __LP64__
+  char __reserved[4];
 #endif
 } mbstate_t;