--- a/source/c_gpio.c
+++ b/source/c_gpio.c
@@ -85,7 +85,7 @@
     if ((uint32_t)gpio_mem % PAGE_SIZE)
         gpio_mem += PAGE_SIZE - ((uint32_t)gpio_mem % PAGE_SIZE);
 
-    gpio_map = (uint32_t *)mmap( (caddr_t)gpio_mem, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, mem_fd, gpio_base);
+    gpio_map = (uint32_t *)mmap( (void *)gpio_mem, BLOCK_SIZE, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_FIXED, mem_fd, gpio_base);
 
     if ((uint32_t)gpio_map < 0)
         return SETUP_MMAP_FAIL;
@@ -233,5 +233,5 @@
 
 void cleanup(void)
 {
-    munmap((caddr_t)gpio_map, BLOCK_SIZE);
+    munmap((void *)gpio_map, BLOCK_SIZE);
 }