-o is not a valid switch for cl

It's deprecated, but still seems to work.

the script doesn't add an extension to $output

I had modified the command to append a '.exe'.

I do not understand at all why they are using IPC::Open3

Nor do I.

Taking your suggestion, I opted to use 'warn' instead of 'print', in case STDOUT was going somewhere other than to the console. When I do: 
warn "# $_" while <$out>;
warn "# $_" while <$err>;

[download]
I get to see that I need to additionally link to bufferoverflowU.lib - and when I modify $cmd to do that, the executable gets built, and all bar one of the 00_ptr_cast.t tests pass: 
ok 1 - compiling ptr_cast_test.c
not ok 2 - STDERR empty after compiling
#   Failed test 'STDERR empty after compiling'
#   at t/local/00_ptr_cast.t line 30.
#          got: undef
#     expected: ''
ok 3 - ./ptr_cast_test exited with 0
ok 4 - casting pointer integer and back worked
ok 5 - STDERR empty after running
# Looks like you failed 1 test of 5.

[download]
Maybe tomorrow I'll look at filing a bug report.
Thanks muchly for the help.

Cheers,
Rob

In reply to Re^4: waitpid on Win32 ... wait forever by syphilis
in thread waitpid on Win32 ... wait forever 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.