foo.cc: In function 'void print()':
foo.cc:9:19: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
 #define fn(i,x,y) for(int i=(x),_=(y);i>=_;--i)
                   ^
foo.cc:42:2: note: in expansion of macro 'fn'
  fn(i,la,1)printf("%lld",a[i]);cout<<endl;
  ^~
foo.cc:42:32: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  fn(i,la,1)printf("%lld",a[i]);cout<<endl;
                                ^~~~