Hi all,

If i do this in my kernel, I get nothing.

```
//pos is the array I am passing in from the host application to the kernel
//F is a constant value
//float4 x_i = pos[index];
//float4 F = make_float4(0,-0.0098,0,0);
float4 newVal = x_i+F;
pos[index] = newVal;
```

If I change it to this,

```
float4 newVal = make_float4(x_i.x+F.x, x_i.y+F.y, x_i.z+F.z, 1.0f);
pos[index] = newVal;
```

I get the correct output. Could anyone tell me why the first version does not work while the second one does?

Regards,

Mobeen