Hi,

At Wed, 20 Dec 2006 07:00:09 +0900,
Steven Jenkins wrote in [ruby-core:09749]:
> Back in August, I needed a semaphore to serialize access to an external
> resource. I found the System V IPC library by Daiki Ueno, and it worked
> well enough on Linux, but wouldn't compile under Solaris. I fixed that
> problem and contacted Daiki, who hadn't updated the package in several
> years. After a little discussion, I created a project (sysvipc) on
> RubyForge and made the updates.

I'm curious about have_type in extconf.rb.

> It prevents false negatives caused by optimization in gcc 4.x.

What do you mean by "false negatives"?  It returns false for an
existing type, or true for a non-existing type?

Does "by optimization" mean `conftestval' is omitted and
ignored completely?

-- 
Nobu Nakada