diff --git a/libc/include/ctype.h b/libc/include/ctype.h
index a66df12..6e97326 100644
--- a/libc/include/ctype.h
+++ b/libc/include/ctype.h
@@ -56,8 +56,6 @@
 __BEGIN_DECLS
 
 extern const char	*_ctype_;
-extern const short	*_tolower_tab_;
-extern const short	*_toupper_tab_;
 
 #if defined(__GNUC__) || defined(_ANSI_LIBRARY) || defined(lint)
 int	isalnum(int);
diff --git a/libc/include/sys/cdefs_elf.h b/libc/include/sys/cdefs_elf.h
index c21214c..b5db13e 100644
--- a/libc/include/sys/cdefs_elf.h
+++ b/libc/include/sys/cdefs_elf.h
@@ -64,6 +64,13 @@
 /* Used to tag non-static symbols that are private and never exposed by the shared library. */
 #define __LIBC_HIDDEN__ __attribute__((visibility ("hidden")))
 
+/* Like __LIBC_HIDDEN__, but preserves binary compatibility for LP32. */
+#ifdef __LP64__
+#define __LIBC64_HIDDEN__ __LIBC_HIDDEN__
+#else
+#define __LIBC64_HIDDEN__
+#endif
+
 /* Used to tag non-static symbols that are public and exposed by the shared library. */
 #define __LIBC_ABI_PUBLIC__ __attribute__((visibility ("default")))
 
diff --git a/libc/upstream-openbsd/android/include/openbsd-compat.h b/libc/upstream-openbsd/android/include/openbsd-compat.h
index 8618e31..f00d91a 100644
--- a/libc/upstream-openbsd/android/include/openbsd-compat.h
+++ b/libc/upstream-openbsd/android/include/openbsd-compat.h
@@ -17,6 +17,8 @@
 #ifndef _BIONIC_OPENBSD_COMPAT_H_included
 #define _BIONIC_OPENBSD_COMPAT_H_included
 
+#include <sys/cdefs.h>
+
 #define __USE_BSD
 
 /* OpenBSD's <ctype.h> uses these names, which conflicted with stlport.
@@ -34,4 +36,8 @@
 /* OpenBSD has this, but we can't really implement it correctly on Linux. */
 #define issetugid() 0
 
+/* LP32 NDK ctype.h contained references to these. */
+__LIBC64_HIDDEN__ extern const short *_tolower_tab_;
+__LIBC64_HIDDEN__ extern const short *_toupper_tab_;
+
 #endif