dereferencing pointer to incomplete type解决方法

错误：

/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c: In function 'scumm_open':
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:54: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:54: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c: In function 'scumm_release':
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:96: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:96: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c: In function 'scumm_read':
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:140: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:140: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c: In function 'scumm_write':
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:210: error: dereferencing pointer to incomplete type
/home/lingd/arm2410s/ldd3/chapter4/scumm/scumm.c:210: error: dereferencing pointer to incomplete type

 

出错语句：

printk(KERN_DEBUG "\"%s(pid %d)\" open scumm device!\n", current->comm, current->pid);

宏current定义在arch/arm/include/asm/current.h中，

static inline struct task_struct *get_current(void)
{
    return current_thread_info()->task;
}

#define current (get_current())

出错原因：
编译器不知道task_struct的具体定义，因此，无法解引用current，无法获知其成员comm、pid的类型，才报“dereferencing pointer to incomplete type”

task_struct定义在中。在源文件头，加上#include ，即可解决问题！

“dereferencing pointer to incomplete type”错误，大多也是因为不知道struct/class/emun/union等的定义而引起的