CPP "problems" (was Re: why has Cray dropped CPP support from cf77?)

[Dik T. Winter]

In article <1300 at red8.qtp.ufl.edu> bernhold at qtp.ufl.edu (David E. Bernholdt) writes:
 > It is worth noting that this difference in blank significance is only
 > relevant when using the macro substitution capabilities of CPP -- the
 > include and conditional compilation features are all given with lines
 > beginning '#' as their first non-blank character.
That is not the only possible problem.  CPP is allowed to remove leading
white space from a line.  There is at least one CPP around that does that
occasionally.  Other problems that might occur are with quotes (both single
and double).  ANSI C preprocessors *must* look at them as starting string/
character constants, disallowing preprocessing within them.  (But this is
of course only a problem if you are using hollerith constants.)
--
dik t. winter, cwi, amsterdam, nederland
dik at cwi.nl