/PREPROCESS_ONLY
       /PREPROCESS_ONLY[=filename]
       /NOPREPROCESS_ONLY (D)

    Causes the compiler to perform only the actions of the
    preprocessor phase and write the resulting processed text out
    to a file. The default output file extension is .IXX. Use of
    /PREPROCESS_ONLY prevents the generation of an object or XREF
    file.