这段二叉树程序，为啥运行不了啊，说*T创建动态内存是是空指针导致程序中断

#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<stdlib.h>
typedef char Elemtype;

typedef struct Bitnote
{
Elemtype data;
struct Bitnites* lchild, * rchild;
}BiTNode,Bitree; //创建一颗二叉树
void CreatBitree(Bitree T)
{
char c = 0;
scanf("%c",c);
if (' ' == c)
(*T) = NULL;
else
{
(T) = (BiTNode)malloc(sizeof(BiTNode));
(*T)->data = 'c';
CreatBitree(&(*T)->lchild);
CreatBitree(&(*T)->rchild);

};

};
void visit(char c, int level)
{
printf("%c位于第%d层",c,level);
}

void Preorder(Bitree T, int level)
{
if(T)
visit(T->data, level);
Preorder(T->lchild, ++level);
Preorder(T->rchild, ++level);
}
int main()
{
int level = 1;
Bitree T=NULL;
CreatBitree(&T);
Preorder(T, level);
return 0;
}