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From: "StevenSun2021 at hotmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/108218] [12/13 Regression] Constant arguments in the new expression is not checked in unevaluated operand
Date: Sat, 24 Dec 2022 20:56:51 +0000	[thread overview]
Message-ID: <bug-108218-4-xceeMUbgfe@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108218-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108218

--- Comment #6 from Steven Sun <StevenSun2021 at hotmail dot com> ---
g:4df7f8c79835d56928f51f9e674d326300936e8e

c++: don't do constexpr folding in unevaluated context

The implicit constexpr patch revealed that we were doing constant evaluation
of arbitrary expressions in unevaluated contexts, leading to failure when we
tried to evaluate e.g. a call to declval.  This is wrong more generally;
only manifestly-constant-evaluated expressions should be evaluated within
an unevaluated operand.

Making this change revealed a case we were failing to mark as manifestly
constant-evaluated.

gcc/cp/ChangeLog:

* constexpr.c (maybe_constant_value): Don't evaluate
in an unevaluated operand unless manifestly const-evaluated.
(fold_non_dependent_expr_template): Likewise.
* decl.c (compute_array_index_type_loc): This context is
manifestly constant-evaluated.

  parent reply	other threads:[~2022-12-24 20:56 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-24 15:52 [Bug c++/108218] New: [12 " StevenSun2021 at hotmail dot com
2022-12-24 16:00 ` [Bug c++/108218] " StevenSun2021 at hotmail dot com
2022-12-24 19:19 ` [Bug c++/108218] [12/13 " pinskia at gcc dot gnu.org
2022-12-24 20:44 ` StevenSun2021 at hotmail dot com
2022-12-24 20:46 ` pinskia at gcc dot gnu.org
2022-12-24 20:49 ` StevenSun2021 at hotmail dot com
2022-12-24 20:56 ` StevenSun2021 at hotmail dot com [this message]
2022-12-24 22:53 ` StevenSun2021 at hotmail dot com
2022-12-27 12:24 ` [Bug c++/108218] [12/13 Regression] Constant arguments in the new expression is not checked in unevaluated operand since r12-5253-g4df7f8c79835d569 marxin at gcc dot gnu.org
2023-01-09 13:42 ` rguenth at gcc dot gnu.org
2023-01-10 15:16 ` ppalka at gcc dot gnu.org
2023-01-10 18:52 ` pinskia at gcc dot gnu.org
2023-01-21 17:22 ` StevenSun2021 at hotmail dot com
2023-01-25  2:59 ` jason at gcc dot gnu.org
2023-01-25  3:19 ` jason at gcc dot gnu.org
2023-03-01 19:09 ` cvs-commit at gcc dot gnu.org
2023-04-28 22:13 ` [Bug c++/108218] [12/13/14 " cvs-commit at gcc dot gnu.org
2023-05-08 12:26 ` rguenth at gcc dot gnu.org

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