diff --git a/src/internal/stdio_impl.h b/src/internal/stdio_impl.h
index cdb0f96b4956e4a7b5dab4c6dc707c3678206822..c3093d01c2189914c329b10af85ec0326b46db10 100644
--- a/src/internal/stdio_impl.h
+++ b/src/internal/stdio_impl.h
@@ -87,6 +87,8 @@ void __register_locked_file(FILE *, struct __pthread *);
 void __unlist_locked_file(FILE *);
 void __do_orphaned_stdio_locks(void);
 
+void __getopt_msg(const char *, const char *, const char *, size_t);
+
 #define feof(f) ((f)->flags & F_EOF)
 #define ferror(f) ((f)->flags & F_ERR)
 
diff --git a/src/misc/getopt_long.c b/src/misc/getopt_long.c
index ddcef9499fe4076d7a9e1b02ff633ac6bcd9eaec..6949ab1c7eec09753b49946da4ceeef6b89e3adc 100644
--- a/src/misc/getopt_long.c
+++ b/src/misc/getopt_long.c
@@ -5,6 +5,7 @@
 #include <getopt.h>
 #include <stdio.h>
 #include <string.h>
+#include "stdio_impl.h"
 
 extern int __optpos, __optreset;
 
@@ -18,8 +19,6 @@ static void permute(char *const *argv, int dest, int src)
 	av[dest] = tmp;
 }
 
-void __getopt_msg(const char *, const char *, const char *, size_t);
-
 static int __getopt_long_core(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx, int longonly);
 
 static int __getopt_long(int argc, char *const *argv, const char *optstring, const struct option *longopts, int *idx, int longonly)