diff --git a/include/psa/crypto_extra.h b/include/psa/crypto_extra.h
index 86d9954..5dd4789 100644
--- a/include/psa/crypto_extra.h
+++ b/include/psa/crypto_extra.h
@@ -30,6 +30,8 @@
 #ifndef PSA_CRYPTO_EXTRA_H
 #define PSA_CRYPTO_EXTRA_H
 
+#include "mbedtls/platform_util.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif