1* KLM rescan with #undef (so rescan is after expansion)
2      integer, parameter :: KWM2 = 777, KWM = 667
3#define KWM2 666
4#define KWM KWM2
5#undef KWM2
6      if (KWM .eq. 777) then
7        print *, 'pp018.F pass'
8      else
9        print *, 'pp018.F FAIL: ', KWM
10      end if
11      end
12