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From: "Stéphane Glondu" <stephane.glondu@inria.fr>
To: Alexander Monakov <amonakov@ispras.ru>, gcc-help@gcc.gnu.org
Cc: sibid@uvic.ca, Paul Zimmermann <Paul.Zimmermann@inria.fr>
Subject: Re: slowdown with -std=gnu18 with respect to -std=c99
Date: Thu, 5 May 2022 16:31:48 +0200	[thread overview]
Message-ID: <c1a686bd-d2fa-a934-f931-6bf96f11e3d9@inria.fr> (raw)
In-Reply-To: <c8517377-e695-06fe-0be4-b7e409d471b9@inria.fr>

As additional data points, the performance with several versions of gcc
(as packaged in Debian testing/unstable):

             | gcc-9 | gcc-10 | gcc-11 | gcc-12 |
 ------------|-------|--------|--------|--------|
  -std=c99   | 24    | 23.5   | 23     | 23     |
  -std=gnu18 | 43    | 16.8   | 38     | 38     |

One can see that the performance stays relatively constant with
-std=c99, but varies significantly with -std=gnu18.

-- 
Stéphane

  reply	other threads:[~2022-05-05 14:31 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-03  8:28 Paul Zimmermann
2022-05-03  9:09 ` Alexander Monakov
2022-05-03 11:45   ` Paul Zimmermann
2022-05-03 12:12     ` Alexander Monakov
2022-05-05  8:57   ` Stéphane Glondu
2022-05-05 14:31     ` Stéphane Glondu [this message]
2022-05-05 14:41       ` Marc Glisse
2022-05-05 14:56         ` Alexander Monakov
2022-05-06  7:46           ` Paul Zimmermann
2022-05-06  9:27             ` Alexander Monakov
2022-05-07  6:11               ` Paul Zimmermann
2022-05-11 13:26               ` Alexander Monakov
2022-05-05 17:50         ` Paul Zimmermann

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