// Slot indices follow declaration order, not first-use order.
uint first = 1;
uint second = 2;
second = second + 1;
first = first + second;
if (first != 4)
  exit(1);

// Shadowed locals use distinct slots in distinct environments.
uint value = 10;
{
  uint value = 20;
  value = value + 1;
  if (value != 21)
    exit(1);
}
if (value != 10)
  exit(1);

// Access an outer local from nested loop/body scopes.
uint total = 0;
for (uint i = 0; i < 4; i = i + 1)
{
  {
    uint nested = i;
    total = total + nested;
  }
}
if (total != 6)
  exit(1);