diff --git a/drivers/readrsa.c b/drivers/readrsa.c
index 566220819aa842489b155b8ce1897b8162cc4fde..188f88eb6cf220bf719e7c3eef59466f68154dba 100644
--- a/drivers/readrsa.c
+++ b/drivers/readrsa.c
@@ -14,6 +14,7 @@
  **/
 #include "common.h"
 #include "spm_drivers.h"
+#include "FCmangle.h"
 
 /**
  * Function: FORTRAN_CALL(wreadmtc)