Hi,

The script: 
use Inline C => Config =>
    CLEAN_AFTER_BUILD => 1,
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

SV * foo(FILE * stream) {
     return newSVuv(42);
}

EOC

print foo(*STDOUT);

[download]
Running on perl 5.6 I get the following warning during compilation: 
try_pl_0446.c: In function `XS_main_foo':
try_pl_0446.c:28: warning: initialization from incompatible pointer ty
+pe

[download]
Looking at the C file I see that line 28 is: 
FILE *    stream = IoIFP(sv_2io(ST(0)));

[download]
The same script, run under perl 5.8 produces no compiler warnings. The corresponding line in the C file is: 
FILE *    stream = PerlIO_findFILE(IoIFP(sv_2io(ST(0))));

[download]
(Note that in both instances the C file was autogenerated by ExtUtils::ParseXS version 2.17.)

Questions:
1) Is there anything I can do to remove that warning with perl 5.6 ?
2) Should I be perturbed by the warning issued with perl 5.6 ?

It's unlikely that the actual demo I've provided is going to suffer from the "incompatible pointer" ... but in the real world, foo() actually *does* something with the FILE* argument. So far, it all seems to work as intended ... but compiler warnings always worry me ...

Cheers,
Rob

In reply to FILE* ... perl 5.6 ... backwards compatibility by syphilis

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.