Problem:Unable to pass structure to a opencl kernel

Unable to pass structure to a opencl kernel?

main.h

typedef struct _Point

{

  unsigned int x;

  unsigned int y;

}mPoint;

kernel.cl:

#include"main.h"

__kernel void Fun(__global struct mPoint* p)

{                               

    unsigned int tid = get_local_id(0);

    p->x=tid;

}

The error returned by clBuildProgram():

clBuild failed:-11

Compilation started

1:3:38: warning: declaration of 'struct mPoint' will not be visible outside of t

his function

1:6:3: error: incomplete definition of type 'struct mPoint'

1:3:38: note: forward declaration of 'struct mPoint'

Compilation failed

I don't known where is the mistake.

Thanks.