Thread: error C2105: '++' needs l-value

Hi, I've problem with compile this code (using VC++ 2010). I've got an error
"error C2105: '++' needs l-value" ... on penultimate row but I can't figurate, what's the problem.

Code:

int Push(double value)
{
	if(stack == NULL)
		return 1;
	if(position+sizeof(double) > stack+size)
		return 1;
	*(double*)position = value;
	((double*)position)++;              // ON THIS LINE I GET ERROR                        
	return 0;
}