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Date: Fri, 22 Apr 2022 19:44:13 +0300 (MSK)
From: Alexander Monakov <amonakov@ispras.ru>
To: Max Sagebaum <max.sagebaum@scicomp.uni-kl.de>
cc: "gcc-help@gcc.gnu.org" <gcc-help@gcc.gnu.org>
Subject: Re: Detect '-fvisibility=hidden' during pre process or compile
 time
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On Fri, 22 Apr 2022, Max Sagebaum wrote:

> Hello Alexander,
> 
> thank you for the answer. Unfortunately, the type needs to be a template
> parameter.  Is there any other way to change the visibility of a member or in
> addition change the visibility of a template parameter?

You can change visibility of the type used as the template parameter; in the
small example in the Bugzilla, you could write

struct __attribute__((visibility("default"))) S {
};

or with a pragma:

#pragma GCC visibility push(default)
struct S {
};
#pragma GCC visibility pop

If in your actual library such 'struct S' has many members and you want to avoid
making them default-visibility, you could move some of them into a subobject
(which then may have hidden visibility).

Alexander