I certainly wouldn't want to encourage more use of the preprocessor. But I can understand having a preprocessor that does something more than whatever's stock

I certainly wouldn't want to encourage more use of the preprocessor. But I can understand having a preprocessor that does something more than whatever's stock on your system (JPL, for instance, has their own C preprocessor: http://lars-lab.jpl.nasa.gov/ http://lars-lab.jpl.nasa.gov/ , scroll down to "released code"), even if it's standard conforming.