diff --git a/include/openssl/bio.h b/include/openssl/bio.h
index 06e1cbf792673615c27b60a902e0493a1e6c569e..3b2265fbabd1b24620f3f508ee9ed6d0ccc88527 100644
--- a/include/openssl/bio.h
+++ b/include/openssl/bio.h
@@ -519,14 +519,14 @@ struct bio_dgram_sctp_prinfo {
  */
 int BIO_read_filename(BIO *b, const char *name);
 # else
-#  define BIO_read_filename(b,name) BIO_ctrl(b,BIO_C_SET_FILENAME, \
+#  define BIO_read_filename(b,name) (int)BIO_ctrl(b,BIO_C_SET_FILENAME, \
                 BIO_CLOSE|BIO_FP_READ,(char *)name)
 # endif
-# define BIO_write_filename(b,name) BIO_ctrl(b,BIO_C_SET_FILENAME, \
+# define BIO_write_filename(b,name) (int)BIO_ctrl(b,BIO_C_SET_FILENAME, \
                 BIO_CLOSE|BIO_FP_WRITE,name)
-# define BIO_append_filename(b,name) BIO_ctrl(b,BIO_C_SET_FILENAME, \
+# define BIO_append_filename(b,name) (int)BIO_ctrl(b,BIO_C_SET_FILENAME, \
                 BIO_CLOSE|BIO_FP_APPEND,name)
-# define BIO_rw_filename(b,name) BIO_ctrl(b,BIO_C_SET_FILENAME, \
+# define BIO_rw_filename(b,name) (int)BIO_ctrl(b,BIO_C_SET_FILENAME, \
                 BIO_CLOSE|BIO_FP_READ|BIO_FP_WRITE,name)
 
 /*