4 files changed, 6 insertions, 0 deletions
diff --git a/libio/bug-wmemstream1.c b/libio/bug-wmemstream1.c
index 2190593c93..22d67f71e9 100644
--- a/libio/bug-wmemstream1.c
+++ b/libio/bug-wmemstream1.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <string.h>
+#include <wchar.h>
 
 
 static int
diff --git a/libio/tst-wmemstream1.c b/libio/tst-wmemstream1.c
index 0c59c1adcb..f8b308bc6c 100644
--- a/libio/tst-wmemstream1.c
+++ b/libio/tst-wmemstream1.c
@@ -1,3 +1,5 @@
+#include <wchar.h>
+
 #define CHAR_T wchar_t
 #define W(o) L##o
 #define OPEN_MEMSTREAM open_wmemstream
diff --git a/libio/tst-wmemstream2.c b/libio/tst-wmemstream2.c
index f51a1db20c..e2442ebfac 100644
--- a/libio/tst-wmemstream2.c
+++ b/libio/tst-wmemstream2.c
@@ -1,3 +1,5 @@
+#include <wchar.h>
+
 #define CHAR_T wchar_t
 #define W(o) L##o
 #define OPEN_MEMSTREAM open_wmemstream
diff --git a/libio/wmemstream.c b/libio/wmemstream.c
index 85ea64991a..577931888d 100644
--- a/libio/wmemstream.c
+++ b/libio/wmemstream.c
@@ -20,6 +20,7 @@
 #include "strfile.h"
 #include <stdio.h>
 #include <stdlib.h>
+#include <wchar.h>
 
 
 struct _IO_FILE_wmemstream