From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 5D350385842B; Fri, 23 Feb 2024 13:41:00 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5D350385842B
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1708695660;
	bh=mo1gZP1GTirq5FXC2Y9esrYgwCBi9gcdnpIROUxXT3U=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=xznNOXZfb8x/74RvQ5sxpARHd5wmUdrz1VUiL1U7W4fPGT5pmjQ+6UQHiqObrsylr
	 PjcmyviKl/AZaFudux1iXR/IbperWNYKPOxAYtNvxYZcFa8uwwFc1trKOQB1pQ2H5M
	 V0ICHErj2Q8wt9vwN5SROl/GI453AwHPW1fMX5X8=
From: "tanksherman27 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/105645] Template specializations are not hidden with
 fvisibility=hidden
Date: Fri, 23 Feb 2024 13:40:57 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 12.1.0
X-Bugzilla-Keywords: visibility
X-Bugzilla-Severity: normal
X-Bugzilla-Who: tanksherman27 at gmail dot com
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-105645-4-IPvDuaN7OR@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-105645-4@http.gcc.gnu.org/bugzilla/>
References: <bug-105645-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105645

Julian Waters <tanksherman27 at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tanksherman27 at gmail dot=
 com

--- Comment #3 from Julian Waters <tanksherman27 at gmail dot com> ---
I can confirm this on gcc 11 and higher:

#include <cstdlib>

template<typename T>
void method(T* src, T* dst, size_t length);

template<>
void method<short>(short* src, short* dst, size_t length) {

}

template<>
void method<int>(int* src, int* dst, size_t length) {

}

Compiled using command line:
g++ -O3 -fvisibility=3Dhidden -std=3Dc++14 -pedantic -Wpedantic -Wall -Werr=
or
templates.cpp

Linked using:
g++ -shared -o libtemplates.so templates.o

When nm is run over it using nm -gDC libtemplates.so, the following symbols=
 are
seen:
                 w _ITM_deregisterTMCloneTable
                 w _ITM_registerTMCloneTable
0000000000001110 T void method<int>(int*, int*, unsigned long)
0000000000001100 T void method<short>(short*, short*, unsigned long)
                 w __cxa_finalize
                 w __gmon_start__

T void method<int>(int*, int*, unsigned long) and T void method<short>(shor=
t*,
short*, unsigned long) should not be in the symbol table, but they are even
with -fvisibility=3Dhidden.

Strangely, marking both methods with [[gnu::visibility("hidden")]] works and
results in both not being exported.

This was recently observed in the JDK, inside the Java HotSpot VM (see
https://github.com/openjdk/jdk/pull/17955/files#r1498933843)

Is this enough of a reproducer to get this confirmed?=