diff --git a/drivers/io/io_fip.c b/drivers/io/io_fip.c
index d291423..99cf15b 100644
--- a/drivers/io/io_fip.c
+++ b/drivers/io/io_fip.c
@@ -128,7 +128,7 @@
 
 
 /* Open a connection to the FIP device */
-static int fip_dev_open(const uintptr_t dev_spec __attribute__((unused)),
+static int fip_dev_open(const uintptr_t dev_spec __unused,
 			 io_dev_info_t **dev_info)
 {
 	assert(dev_info != NULL);
diff --git a/drivers/io/io_memmap.c b/drivers/io/io_memmap.c
index d45107e..ff4efa8 100644
--- a/drivers/io/io_memmap.c
+++ b/drivers/io/io_memmap.c
@@ -95,7 +95,7 @@
 
 
 /* Open a connection to the memmap device */
-static int memmap_dev_open(const uintptr_t dev_spec __attribute__((unused)),
+static int memmap_dev_open(const uintptr_t dev_spec __unused,
 			   io_dev_info_t **dev_info)
 {
 	assert(dev_info != NULL);
diff --git a/drivers/io/io_semihosting.c b/drivers/io/io_semihosting.c
index 63d0f68..30ca99c 100644
--- a/drivers/io/io_semihosting.c
+++ b/drivers/io/io_semihosting.c
@@ -91,7 +91,7 @@
 
 
 /* Open a file on the semi-hosting device */
-static int sh_file_open(io_dev_info_t *dev_info __attribute__((unused)),
+static int sh_file_open(io_dev_info_t *dev_info __unused,
 		const uintptr_t spec, io_entity_t *entity)
 {
 	int result = -ENOENT;