diff --git a/example/main.c b/example/main.c
index 71fbdee..c327a7c 100644
--- a/example/main.c
+++ b/example/main.c
@@ -3,7 +3,7 @@
 #include <wchar.h>
 #include <locale.h>
 
-static FTABLE *create_basic_table()
+static FTABLE *create_basic_table(void)
 {
     FTABLE *table = ft_create_table();
     ft_set_cell_option(table, FT_ANY_ROW, 0, FT_COPT_TEXT_ALIGN, FT_ALIGNED_CENTER);
diff --git a/src/options.c b/src/options.c
index 3a05ad7..a6fbfa4 100644
--- a/src/options.c
+++ b/src/options.c
@@ -364,7 +364,7 @@ fort_table_options_t g_table_options = {
 };
 
 
-fort_table_options_t *create_table_options()
+fort_table_options_t *create_table_options(void)
 {
     fort_table_options_t *options = (fort_table_options_t *)F_CALLOC(sizeof(fort_table_options_t), 1);
     if (options == NULL) {
diff --git a/src/options.h b/src/options.h
index 3bc1845..72e8e0f 100644
--- a/src/options.h
+++ b/src/options.h
@@ -146,7 +146,7 @@ extern fort_table_options_t g_table_options;
 
 
 
-fort_table_options_t* create_table_options();
+fort_table_options_t* create_table_options(void);
 fort_table_options_t* copy_table_options(const fort_table_options_t *option);
 void destroy_table_options(fort_table_options_t* options);
 
diff --git a/tests/test_memory_errors.c b/tests/test_memory_errors.c
index d50f52a..943a9e3 100644
--- a/tests/test_memory_errors.c
+++ b/tests/test_memory_errors.c
@@ -23,7 +23,7 @@ void test_free(void *ptr)
     }
 }
 
-static int create_simple_table_and_show()
+static int create_simple_table_and_show(void)
 {
     FTABLE *table = NULL;
     int result = 0;