From: L A Walsh <gcc@tlinx.org>
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Jonathan Wakely <jwakely.gcc@gmail.com>,
gcc-help <gcc-help@gcc.gnu.org>,
unlvsur unlvsur <unlvsur@live.com>
Subject: Re: how to get -march=native's value?
Date: Mon, 27 Sep 2021 11:14:54 -0700 [thread overview]
Message-ID: <61520A1E.9050900@tlinx.org> (raw)
In-Reply-To: <20210927171344.GA8185@gate.crashing.org>
On 2021/09/27 10:13, Segher Boessenkool wrote:
> On Mon, Sep 27, 2021 at 02:55:28PM +0200, Vincent Lefevre wrote:
>
>> On 2021-09-17 12:53:25 -0500, Segher Boessenkool wrote:
>>
>>> For x86 -march=something is the same as -march=native, _if_ the compiler
>>> knows about your CPU.
>>>
----
I have a question, as someone reading this conversation ....
If one is using cross-compilation -- as it sounded like the original
author might be doing, what could the compiler know about the target
machine?
Is there some sort of "profile-this-cpu-for-pertinent-options" binary
or compiler-option that one should(or could) run on the target
machine in order that the correct compiler switches be set?
Otherwise, it would seem that -march=native would only be useful for
the (probably majority of) cases where one is compiling for their own
machine (?).
next prev parent reply other threads:[~2021-09-27 18:16 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-07 7:02 unlvsur unlvsur
2021-09-07 7:56 ` Jonathan Wakely
2021-09-17 2:46 ` NightStrike
2021-09-17 8:29 ` Xi Ruoyao
2021-09-17 10:26 ` Jonathan Wakely
2021-09-17 10:38 ` Jonathan Wakely
2021-09-17 17:53 ` Segher Boessenkool
2021-09-27 12:55 ` Vincent Lefevre
2021-09-27 17:13 ` Segher Boessenkool
2021-09-27 18:14 ` L A Walsh [this message]
2021-09-27 18:25 ` Jonathan Wakely
2021-09-27 20:26 ` Segher Boessenkool
2021-09-27 20:30 ` NightStrike
2021-09-27 18:26 ` Florian Weimer
2021-09-07 7:59 ` Hongtao Liu
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