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c++ - Preprocessor bug with -A: //*

With dmc -A, this is fine:

    #if 0

and this:

    #if 0 //*

and this:

    #define X //*

but this one fails:

    #if 0
    #endif //*

and this, too:

    #if 0
    #else //*


    Lexical error: end of file found before end of comment, line 1
    Fatal error: premature end of source file

(I found this very annoying while trying to use STLPort.)

Also with -A:

    Lexical error: last line in file had no \n

I feel this should not be an error (unless the warning level
is bumped up to warnings --> errors).

The std says:

    "If a source file that is not empty does not end in a
    new-line character [...] the behavior is undefined."

So, it does not mandate an error. And, as to using this
error as a portability aid: in practice, I have never
heared of such a sloppy compiler that could not cope with
it. If still there exists one, it is probably never ever
get used by the same nice folks who also use DMC ;) , so
trying to alert them does no good. It only annoys. (And
helps authors of lame text processing tools to find cheap
excuses for not handling EOF-terminated last lines correctly.)

Nov 01 2003