diff --git a/libc/include/string.h b/libc/include/string.h
index 7727c0e..af1c0c1 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -31,6 +31,7 @@
 #include <sys/cdefs.h>
 #include <stddef.h>
 #include <malloc.h>
+#include <xlocale.h>
 
 __BEGIN_DECLS
 
@@ -88,6 +89,9 @@
 extern int    strcoll(const char *, const char *) __purefunc;
 extern size_t strxfrm(char* __restrict, const char* __restrict, size_t);
 
+extern int    strcoll_l(const char *, const char *, locale_t) __purefunc;
+extern size_t strxfrm_l(char* __restrict, const char* __restrict, size_t, locale_t);
+
 #if defined(__BIONIC_FORTIFY)
 
 __errordecl(__memcpy_dest_size_error, "memcpy: prevented write past end of buffer");