bug in CTZ

CTZ is not correct for unsigned types such as uint!

Example:

noinline
int foo( uint a)
{
   b = _lt_SxS_ ( 0ui, a);

   return _toi_S_( b);
}


int main ()
{
    return foo( 2ui );
}

CTZ turns the body into (sac2c -bopt):

int _MAIN::foo( uint a { ,NN } )
/*
 *  foo ::  ---
 */
{
  uint _esd_13 { , NN } ;
  int _flat_1 { , NN } ;
  bool b { , NN } ;

  _esd_13 = _neg_S_( a);
  b = _lt_SxS_( _esd_13, 0ui);
  _flat_1 = _toi_S_( b);
  return( _flat_1);
}

which clearly is not legal as neg_S is illegal. The fact that the type inference does not complain about it shows that the type inference is not correct for neg on unsigned types either :-) So it is two bugs for the price of one.