diff --git a/common/tf_printf.c b/common/tf_printf.c
index 02461c0bc2d7564edd77ae83aab9dac63cfd1cef..c68b99044437f79c217508fca56868923125525d 100644
--- a/common/tf_printf.c
+++ b/common/tf_printf.c
@@ -38,7 +38,7 @@ static void unsigned_num_print(unsigned long int unum, unsigned int radix)
 {
 	/* Just need enough space to store 64 bit decimal integer */
 	unsigned char num_buf[20];
-	int i = 0 , rem;
+	int i = 0, rem;
 
 	do {
 		rem = unum % radix;
diff --git a/plat/fvp/fvp_pm.c b/plat/fvp/fvp_pm.c
index 9044e6938d8e30a1e59ccc628e3ea39ada8f3b03..c15d845d80426de298f000a07def61ad46cda679 100644
--- a/plat/fvp/fvp_pm.c
+++ b/plat/fvp/fvp_pm.c
@@ -64,7 +64,7 @@ static void fvp_program_mailbox(uint64_t mpidr, uint64_t address)
  * Function which implements the common FVP specific operations to power down a
  * cpu in response to a CPU_OFF or CPU_SUSPEND request.
  ******************************************************************************/
-static void fvp_cpu_pwrdwn_common()
+static void fvp_cpu_pwrdwn_common(void)
 {
 	/* Prevent interrupts from spuriously waking up this cpu */
 	arm_gic_cpuif_deactivate();
@@ -77,7 +77,7 @@ static void fvp_cpu_pwrdwn_common()
  * Function which implements the common FVP specific operations to power down a
  * cluster in response to a CPU_OFF or CPU_SUSPEND request.
  ******************************************************************************/
-static void fvp_cluster_pwrdwn_common()
+static void fvp_cluster_pwrdwn_common(void)
 {
 	uint64_t mpidr = read_mpidr_el1();
 
diff --git a/plat/juno/bl31_plat_setup.c b/plat/juno/bl31_plat_setup.c
index ad8ea4351ddd41a3efbd755985ecb6980406c119..1d337688d726aded228a668bf61b75183c9be470 100644
--- a/plat/juno/bl31_plat_setup.c
+++ b/plat/juno/bl31_plat_setup.c
@@ -182,7 +182,7 @@ void bl31_platform_setup(void)
  * Perform the very early platform specific architectural setup here. At the
  * moment this is only intializes the mmu in a quick and dirty way.
  ******************************************************************************/
-void bl31_plat_arch_setup()
+void bl31_plat_arch_setup(void)
 {
 	configure_mmu_el3(BL31_RO_BASE,
 			  (BL31_END - BL31_RO_BASE),
diff --git a/plat/juno/plat_topology.c b/plat/juno/plat_topology.c
index c22edda2d4bf4ae1cddd6fed340bc182baeaba3b..24be767054ec56ec7e6b3bf5fd9e42d6d2f19f84 100644
--- a/plat/juno/plat_topology.c
+++ b/plat/juno/plat_topology.c
@@ -48,7 +48,7 @@ unsigned int plat_get_aff_state(unsigned int aff_lvl, unsigned long mpidr)
 	return aff_lvl <= MPIDR_AFFLVL1 ? PSCI_AFF_PRESENT : PSCI_AFF_ABSENT;
 }
 
-int plat_setup_topology()
+int plat_setup_topology(void)
 {
 	/* Juno todo: Make topology configurable via SCC */
 	return 0;
diff --git a/services/std_svc/psci/psci_afflvl_suspend.c b/services/std_svc/psci/psci_afflvl_suspend.c
index dad0cefd86c948596a81f25859bb772fc9d3a535..76e8c908a0d9a4776c822e29cfd822d8f08a81cc 100644
--- a/services/std_svc/psci/psci_afflvl_suspend.c
+++ b/services/std_svc/psci/psci_afflvl_suspend.c
@@ -58,7 +58,7 @@ void psci_set_suspend_power_state(unsigned int power_state)
  * powered down during a cpu_suspend call. Returns PSCI_INVALID_DATA if the
  * power state is invalid.
  ******************************************************************************/
-int psci_get_suspend_afflvl()
+int psci_get_suspend_afflvl(void)
 {
 	unsigned int power_state;
 
@@ -73,7 +73,7 @@ int psci_get_suspend_afflvl()
  * parameter saved in the per-cpu data array. Returns PSCI_INVALID_DATA if the
  * power state saved is invalid.
  ******************************************************************************/
-int psci_get_suspend_stateid()
+int psci_get_suspend_stateid(void)
 {
 	unsigned int power_state;
 
diff --git a/services/std_svc/psci/psci_common.c b/services/std_svc/psci/psci_common.c
index 7ab607dbac16ee1454e19a3d2c7f0e8be857cbca..237cf1e952fb69c99041b06db9d4588a5c7f1e73 100644
--- a/services/std_svc/psci/psci_common.c
+++ b/services/std_svc/psci/psci_common.c
@@ -133,7 +133,7 @@ uint32_t psci_get_max_phys_off_afflvl(void)
  * been physically powered up. It is expected to be called immediately after
  * reset from assembler code.
  ******************************************************************************/
-int get_power_on_target_afflvl()
+int get_power_on_target_afflvl(void)
 {
 	int afflvl;