OrionLibC

diff --git a/include/stdlib.h b/include/stdlib.h
index b1265c2..7e278b0 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -1,6 +1,8 @@
 #ifndef _STDLIB_H
 #define _STDLIB_H
 
+#include <stddef.h>
+
 #define EXIT_SUCCESS 0
 #define EXIT_FAILURE 1
 
@@ -11,12 +13,13 @@ extern "C" {
 _Noreturn void abort(void);
 int atexit(void (*)(void));
 int atoi(const char *);
-void free(void *);
+void free(void *addr);
 char *getenv(const char *);
-void *malloc(size_t);
+void *malloc(size_t size);
 void *calloc(size_t, size_t);
+void *realloc(void *addr, size_t size);
 _Noreturn void exit(int status);
-int abs(int);
+int abs(int num);
 
 #ifdef __cplusplus
 }