Linux dereferencing pointer to incomplete type error

When modifying the kernel, make uimage encountered such an error:

"Dereferencing pointer to incomplete type"

The explanation for this error is: Your pointer, there is a type, this type is not complete. That is to say, we have only given

This type of declaration does not give its definition. The types here are mostly structures, unions and things like that.

This error is due to the fact that a struct or Union field name refers to a variable-defined header file that is not introduced to the current C-generation

Errors caused by the code, as long as the corresponding variable is found in the struct or the federated definition of the header file, and put these headers

The file is included to resolve this issue.

Linux dereferencing pointer to incomplete type error