/DIAGNOSTICS[=filespec]
       /NODIAGNOSTICS (default)

    Creates a file containing assembler messages and diagnostic
    information. If you omit the file specification, the default file
    name is the same as the source program; the default file type is
    DIA.

    No wildcard characters are allowed in the file specification.

    The diagnostics file is reserved for use with layered products,
    such as the VAX Language-Sensitive Editor (LSE).