From: Segher Boessenkool <segher@kernel.crashing.org>
To: "Shrader, David Lee" <dshrader@lanl.gov>
Cc: "gcc-help@gcc.gnu.org" <gcc-help@gcc.gnu.org>
Subject: Re: [EXTERNAL] Re: question about knowing when optimization options are used
Date: Mon, 16 Mar 2020 19:36:12 -0500 [thread overview]
Message-ID: <20200317003612.GF22482@gate.crashing.org> (raw)
In-Reply-To: <a7d22093615a49de903baea286bc5e40@lanl.gov>
Hi!
On Mon, Mar 16, 2020 at 11:55:01PM +0000, Shrader, David Lee wrote:
> Thank you for the reply. So, what you're saying is that the output of `gcc -Q --help=optimizers` doesn't necessarily reflect what optimization gcc is going to do when -O0 is being used, correct? This is because no (or very little) optimization is actually allowed to be done when -O0 is use.
Yes. Some of the documentation isn't clear on this, but in context it
should be clear?
Segher
next prev parent reply other threads:[~2020-03-17 0:36 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-16 23:14 Shrader, David Lee
2020-03-16 23:34 ` Segher Boessenkool
2020-03-16 23:55 ` [EXTERNAL] " Shrader, David Lee
2020-03-17 0:36 ` Segher Boessenkool [this message]
2020-03-17 1:39 ` Shrader, David Lee
2020-03-17 1:35 ` Jeffrey Walton
2020-03-17 1:44 ` Shrader, David Lee
2020-03-17 2:58 ` Segher Boessenkool
2020-03-17 12:22 ` Richard Sandiford
2020-03-18 20:15 ` Segher Boessenkool
2020-03-18 17:44 ` mark_at_yahoo
2020-03-18 21:24 ` Segher Boessenkool
2020-03-19 14:17 ` Jonathan Wakely
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