From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 04B123858D32; Mon, 12 Feb 2024 15:00:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 04B123858D32 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1707750027; bh=TvaqgzWJRGq1MTLaR5Dsi27RBiYL7oipji7z23ZP+eI=; h=From:To:Subject:Date:In-Reply-To:References:From; b=qB+RkDz+VxIEKMx/uN3ppGQTMMYcjyd5QaDJFjzhFmih6LsYD3t/apAKmoggqqiLN n7kHny2k9OdOTjgOjY9H72zohELznMO2uyL2CWEgciZu1Agh7bYcd21dcjxKSSBoSJ EL08XnzX0WO0acvavlqS04buEYroPgMuWbXaK720= From: "ppalka at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/113835] [13/14 Regression] compiling std::vector with const size in C++20 is slow Date: Mon, 12 Feb 2024 15:00:26 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: libstdc++ X-Bugzilla-Version: 13.2.1 X-Bugzilla-Keywords: compile-time-hog X-Bugzilla-Severity: normal X-Bugzilla-Who: ppalka 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: 13.3 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: 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: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113835 --- Comment #4 from Patrick Palka --- r13-6421 just makes us use mce_true and mce_uknown during trial constant evaluation of x's initialization, so my guess is before that commit the evaluation was quickly aborted as soon as it saw a std::is_constant_evaluat= ed() call, and afterwards we evaluate is_constant_evaluated() to true and keep g= oing until we hit constexpr_loop_limit / constexpr_ops_limit. So perhaps we sho= uld have reduced limits for trial constant evaluation?=