along the perl.h header file installed on you system, you will find config.h (for instance, in my Debian box it is at /usr/lib/perl/5.10.0/CORE/config.h) containing all the information captured by Configure when perl was built.

Specifically it has information about the size of most common C integer types. For instance: 

#define INTSIZE 4               /**/
#define LONGSIZE 4              /**/
#define SHORTSIZE 2             /**/

[download]
BTW, the same information is available on the Perl side using the Config module.

You could also explicitly discard the upper bits from a possible 64bits word using... 

v &= 0xffffffff;

[download]
and hope that the optimizer removes the superfluous instructions from the final code on 32 bit architectures

In reply to Re: Perl XS portable uint32_t by salva
in thread Perl XS portable uint32_t by tachyon-II

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.