Public Comment Number PC-UK0087

ISO/IEC CD 9899 (SC22N2620) Public Comment

=========================================== 

Date: 1998-02-25
Author: N.M Maclaren
Author Affiliation: Self
Postal Address:
    University of Cambridge,
    Computer Laboratory,
    New Museums Site,
    Pembroke Street,
    Cambridge CB3 3QG,
    United Kingdom
E-mail Address: <nmm1@cam.ac.uk>
Telephone Number: +44 1223 334761
Fax Number:       +44 1223 334679
Number of individual comments: 1


Comment 1. 

Category: Feature that should be included

Committee Draft subsection: 7.4.4

Title: Macros for format specifiers


Detailed description:

These are all very well, but this is a major quiet change and not a welcome
one, either.  In C89, long is guaranteed to be the longest integer type, 
and it is possible to cast to long and use a simple format to print any
integer.  C9X abolishes this, and will break many programs.  Even when they
are rewritten, their formats will become unreadable.  I suggest one of two
solutions:

    1) Restore the requirement that long is the longest integer type

or:

    2) Introduce %md, %mu, %mx etc. for the ***MAX forms to alleviate the
pain, as has been suggested.  This is still a change, but should cause less
opposition.

Doing BOTH enables programmers to convert their code to using intmax_t
during the life of C9X, which leaves the option open for a future revision
of the C standard to reintroduce 'long long' with minimum incompatibility,
and is what I should prefer.

The current proposal forces immediate and serious incompatibility, breaks
existing and important conforming code, and makes it impossible to convert
it cleanly to C9X.