diff --git a/src/wolfio.c b/src/wolfio.c
index 158252974f..7376d171c1 100644
--- a/src/wolfio.c
+++ b/src/wolfio.c
@@ -30,6 +30,10 @@
 
 #include <wolfssl/wolfcrypt/settings.h>
 
+#ifdef HAVE_ERRNO_H
+    #include <errno.h>
+#endif
+
 #ifndef WOLFCRYPT_ONLY
 
 #ifdef _WIN32_WCE