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 20CE0388E831; Tue,  5 May 2020 13:24:27 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 20CE0388E831
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
 s=default; t=1588685067;
 bh=hTEOzzS8Th8QVEoWQE9UhROgpcjT9jFjAZ65uHTP+ls=;
 h=From:To:Subject:Date:In-Reply-To:References:From;
 b=iO+D3oF3ffEJ7nie1vqg2pNEeCcZ72dweMFv2G+UJPNnWBzI0DWmVFJ9daDzNy5Um
 EnB8IaXBqaf+8dHYi06Lz/kW91JmM0DzI8VRYErvdPl2npEB1lCbV93jBTf76Jccgi
 wb4gjEiV6iyqTMHwKRHBWAiw/z81/Eq/eiLBOol8=
From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug bootstrap/91972] Bootstrap should use -Wmissing-declarations
Date: Tue, 05 May 2020 13:24:27 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: bootstrap
X-Bugzilla-Version: 10.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: redi at gcc dot gnu.org
X-Bugzilla-Status: NEW
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: 
Message-ID: <bug-91972-4-rOaZh6EWzK@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-91972-4@http.gcc.gnu.org/bugzilla/>
References: <bug-91972-4@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
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <http://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <http://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Tue, 05 May 2020 13:24:27 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D91972

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Alexander Monakov from comment #0)
> Transition to C++ did not change -Wmissing-prototypes to
> -Wmissing-declarations, so over time several violations crept in. In
> particular this penalizes optimization during non-LTO bootstrap (the
> compiler has to assume the function might be used in another TU, even tho=
ugh
> in reality all uses are in current file and it simply misses the 'static'
> keyword).

Why is it missing the static keyword then? (Or alternatively, why isn't it =
in
an anonymous namespace?)


(In reply to Alexander Monakov from comment #1)
> Another reason to have -Wmissing-declarations is that otherwise mismatches
> of unused functions are not caught until it's too late (mismatching
> definition is assumed to be an overload of the function declared in the
> header file).

A more robust way to avoid that problem is to declare the function in a
namespace, and define it using a qualified name:

// declaration
namespace targ
{
  void foo(void*);
}

// definition
void targ::foo(class vec_info*);  // ERROR

Because no foo with that signature was declared in namespace targ it's an
error, not just a warning.

Should the coding convention be adjusted to avoid this problem?=