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 338DA3857BA1; Thu, 26 May 2022 13:38:41 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 338DA3857BA1
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug preprocessor/105732] [9/10/11/12/13 Regression] internal
 compiler error: unspellable token PADDING
Date: Thu, 26 May 2022 13:38:40 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: preprocessor
X-Bugzilla-Version: 11.3.0
X-Bugzilla-Keywords: ice-on-valid-code
X-Bugzilla-Severity: blocker
X-Bugzilla-Who: jakub 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: 9.5
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-105732-4-AZbsMzP3A3@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-105732-4@http.gcc.gnu.org/bugzilla/>
References: <bug-105732-4@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: <https://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: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Thu, 26 May 2022 13:38:41 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105732

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at gcc dot gnu.org

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
With a slightly modified testcase:
#define m1(p1, p2, p3) p3
#define m2(p1, ...) 1 __VA_OPT__()
#define M(...) m1(1, 2, m2)
#if M(,)(,)
#endif
it started to ICE already with r8-6791-g60887f8c2df851 aka PR83708 fix.

The r12-6155-g5545d1edcbdb17 change just turns that into the same tokens as
before, while previously it wasn't.  As __VA_OPT__() or __VA_OPT__(foo) in =
both
cases expands to nothing, 1##nothing is still 1 and the avoid_paste token is
added afterwards to make sure token after __VA_OPT__() isn't emitted right
after it without whitespace.

It isn't immediately clear to me what should be eating the padding token so
that
cpp_parse_expr doesn't see it.

Or is this a bug in cpp_parse_expr?
I mean, other callers of cpp_get_token_with_location like e.g. in
c_lex_with_flags handle CPP_PADDING by calling cpp_get_token_with_location
again.
Similarly scan_translation_unit when doing -E, token_streamer::stream just
remembers there was padding and goes on (and takes that into account whether
whitespace should be emitted or not).=