From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: Christopher Sigman <c.s.sigman@gmail.com>
Cc: gcc-help@gcc.gnu.org
Subject: Re: Warning message with usage of visibility hidden with wrapper class
Date: Thu, 31 May 2012 09:03:00 -0000 [thread overview]
Message-ID: <CAH6eHdRXBgeP8UyyipnVKM5MNyRCD1XB4xwBYvM-AL+g4x9K4w@mail.gmail.com> (raw)
In-Reply-To: <CALvcSj91p6t9SC03pAoRY=q0eP=Z4euWyRHXH2z9E1ML-FJ9jw@mail.gmail.com>
On 31 May 2012 02:42, Christopher Sigman <c.s.sigman@gmail.com> wrote:
> Hi everyone,
>
> Attached is some example code that exhibits the issue. In terms of
A simpler example is
struct __attribute__ ((visibility("hidden"))) Hidden
{
int something;
};
template <typename T>
struct Visible
{
Hidden inner;
};
int main()
{
Visible<int> i;
}
> GCC versions, I think we've seen it in everything from 4.1.2 on, but I
> know for a fact that I see it in 4.4.x, and 4.5.1. I know that if I
It's still present in the latest versions.
> add -fvisibility=hidden to compilation of anything linking to the
> library resolves the warning,
That's because it gives Visible<int> hidden visibility.
> but as I said before, I'm trying to
> understand why we're getting the warning with it as it is (in our
> actual code, we can't set the default visibility to hidden on
> libraries or executables linking to those libraries at the moment).
The compiler is warning you that if you're trying to make Visible<int>
visible outside a shared library then one of its members has hidden
visibility and can't be exported. It's irrelevant that it's a private
member.
prev parent reply other threads:[~2012-05-31 9:03 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-24 2:02 Christopher Sigman
2012-05-24 10:05 ` Jonathan Wakely
2012-05-31 1:42 ` Christopher Sigman
2012-05-31 9:03 ` Jonathan Wakely [this message]
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