diff --git a/driver/others/blas_l1_thread.c b/driver/others/blas_l1_thread.c
index 06039c952..01b254f5d 100644
--- a/driver/others/blas_l1_thread.c
+++ b/driver/others/blas_l1_thread.c
@@ -43,7 +43,7 @@
 int blas_level1_thread(int mode, BLASLONG m, BLASLONG n, BLASLONG k, void *alpha,
 		       void *a, BLASLONG lda,
 		       void *b, BLASLONG ldb,
-		       void *c, BLASLONG ldc, int (*function)(), int nthreads){
+		       void *c, BLASLONG ldc, int (*function)(void), int nthreads){
 
   blas_queue_t queue[MAX_CPU_NUMBER];
   blas_arg_t   args [MAX_CPU_NUMBER];
@@ -141,7 +141,7 @@ int blas_level1_thread(int mode, BLASLONG m, BLASLONG n, BLASLONG k, void *alpha
 int blas_level1_thread_with_return_value(int mode, BLASLONG m, BLASLONG n, BLASLONG k, void *alpha,
 		       void *a, BLASLONG lda,
 		       void *b, BLASLONG ldb,
-		       void *c, BLASLONG ldc, int (*function)(), int nthreads){
+		       void *c, BLASLONG ldc, int (*function)(void), int nthreads){
 
   blas_queue_t queue[MAX_CPU_NUMBER];
   blas_arg_t   args [MAX_CPU_NUMBER];
diff --git a/driver/others/blas_server.c b/driver/others/blas_server.c
index a8a84acbb..2fcb37192 100644
--- a/driver/others/blas_server.c
+++ b/driver/others/blas_server.c
@@ -93,7 +93,7 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #endif
 #endif
 
-extern unsigned int openblas_thread_timeout();
+extern unsigned int openblas_thread_timeout(void);
 
 #ifdef SMP_SERVER
 
diff --git a/driver/others/memory.c b/driver/others/memory.c
index b27fec431..a74cdabd4 100644
--- a/driver/others/memory.c
+++ b/driver/others/memory.c
@@ -1999,7 +1999,7 @@ int  goto_get_num_procs  (void) {
   return blas_cpu_number;
 }
 
-void openblas_fork_handler()
+void openblas_fork_handler(void)
 {
   // This handler shuts down the OpenBLAS-managed PTHREAD pool when OpenBLAS is
   // built with "make USE_OPENMP=0".
@@ -2016,9 +2016,9 @@ void openblas_fork_handler()
 #endif
 }
 
-extern int openblas_num_threads_env();
-extern int openblas_goto_num_threads_env();
-extern int openblas_omp_num_threads_env();
+extern int openblas_num_threads_env(void);
+extern int openblas_goto_num_threads_env(void);
+extern int openblas_omp_num_threads_env(void);
 
 int blas_get_cpu_number(void){
 #if defined(OS_LINUX) || defined(OS_WINDOWS) || defined(OS_FREEBSD) || defined(OS_OPENBSD) || defined(OS_NETBSD) || defined(OS_DRAGONFLY) || defined(OS_DARWIN) || defined(OS_ANDROID) || defined(OS_HAIKU)
@@ -3339,7 +3339,7 @@ static void gotoblas_memory_init(void) {
 /* Initialization for all function; this function should be called before main */
 
 static int gotoblas_initialized = 0;
-extern void openblas_read_env();
+extern void openblas_read_env(void);
 
 void CONSTRUCTOR gotoblas_init(void) {
 
diff --git a/driver/others/openblas_env.c b/driver/others/openblas_env.c
index 35b2270d4..c65f0f320 100644
--- a/driver/others/openblas_env.c
+++ b/driver/others/openblas_env.c
@@ -41,15 +41,15 @@ static int openblas_env_goto_num_threads=0;
 static int openblas_env_omp_num_threads=0;
 static int openblas_env_omp_adaptive=0;
 
-int openblas_verbose() { return openblas_env_verbose;}
-unsigned int openblas_thread_timeout() { return openblas_env_thread_timeout;}
-int openblas_block_factor() { return openblas_env_block_factor;}
-int openblas_num_threads_env() { return openblas_env_openblas_num_threads;}
-int openblas_goto_num_threads_env() { return openblas_env_goto_num_threads;}
-int openblas_omp_num_threads_env() { return openblas_env_omp_num_threads;}
-int openblas_omp_adaptive_env() { return openblas_env_omp_adaptive;}
+int openblas_verbose(void) { return openblas_env_verbose;}
+unsigned int openblas_thread_timeout(void) { return openblas_env_thread_timeout;}
+int openblas_block_factor(void) { return openblas_env_block_factor;}
+int openblas_num_threads_env(void) { return openblas_env_openblas_num_threads;}
+int openblas_goto_num_threads_env(void) { return openblas_env_goto_num_threads;}
+int openblas_omp_num_threads_env(void) { return openblas_env_omp_num_threads;}
+int openblas_omp_adaptive_env(void) { return openblas_env_omp_adaptive;}
 
-void openblas_read_env() {
+void openblas_read_env(void) {
   int ret=0;
   env_var_t p;
   if (readenv(p,"OPENBLAS_VERBOSE")) ret = atoi(p);
diff --git a/driver/others/openblas_error_handle.c b/driver/others/openblas_error_handle.c
index 9ac72c15d..aa0aa776a 100644
--- a/driver/others/openblas_error_handle.c
+++ b/driver/others/openblas_error_handle.c
@@ -33,7 +33,7 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "common.h"
 
-extern int openblas_verbose();
+extern int openblas_verbose(void);
 
 void openblas_warning(int verbose, const char * msg) {
   int current_verbose;
diff --git a/driver/others/openblas_get_config.c b/driver/others/openblas_get_config.c
index 7a5cbeb62..867d0e361 100644
--- a/driver/others/openblas_get_config.c
+++ b/driver/others/openblas_get_config.c
@@ -69,13 +69,13 @@ static char* openblas_config_str=""
   ;
 
 #ifdef DYNAMIC_ARCH
-char *gotoblas_corename();
+char *gotoblas_corename(void);
 #endif
 
 static char tmp_config_str[256];
-int openblas_get_parallel();
+int openblas_get_parallel(void);
 
-char* CNAME() {
+char* CNAME(void) {
 char tmpstr[20];
   strcpy(tmp_config_str, openblas_config_str);
 #ifdef DYNAMIC_ARCH
@@ -90,7 +90,7 @@ char tmpstr[20];
 }
 
 
-char* openblas_get_corename() {
+char* openblas_get_corename(void) {
 #ifndef DYNAMIC_ARCH 
   return CHAR_CORENAME;
 #else
diff --git a/driver/others/openblas_get_parallel.c b/driver/others/openblas_get_parallel.c
index 5dfda6e59..becfa0a3a 100644
--- a/driver/others/openblas_get_parallel.c
+++ b/driver/others/openblas_get_parallel.c
@@ -42,17 +42,17 @@ static int parallel = 0;
 
 
 #ifdef NEEDBUNDERSCORE
-int CNAME() {
+int CNAME(void) {
   return parallel;
 }
 
-int NAME() {
+int NAME(void) {
   return parallel;
 }
 
 #else
 //The CNAME and NAME are the same.
-int NAME() {
+int NAME(void) {
   return parallel;
 }
 #endif
diff --git a/driver/others/parameter.c b/driver/others/parameter.c
index 0d5c6aec0..de6bf0de4 100644
--- a/driver/others/parameter.c
+++ b/driver/others/parameter.c
@@ -40,7 +40,7 @@
 #include <string.h>
 #include "common.h"
 
-extern int openblas_block_factor();
+extern int openblas_block_factor(void);
 int get_L2_size(void);
 
 #define DEFAULT_GEMM_P 128