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From: Richard Sandiford <richard.sandiford@arm.com>
To: Segher Boessenkool <segher@kernel.crashing.org>
Mail-Followup-To: Segher Boessenkool <segher@kernel.crashing.org>,Bernd Edlinger <bernd.edlinger@hotmail.de>,  Jakub Jelinek <jakub@redhat.com>,  Dimitar Dimitrov <dimitar@dinux.eu>,  Christophe Lyon <christophe.lyon@linaro.org>,  Thomas Preudhomme <thomas.preudhomme@linaro.org>,  "gcc-patches\@gcc.gnu.org" <gcc-patches@gcc.gnu.org>, richard.sandiford@arm.com
Cc: Bernd Edlinger <bernd.edlinger@hotmail.de>,  Jakub Jelinek <jakub@redhat.com>,  Dimitar Dimitrov <dimitar@dinux.eu>,  Christophe Lyon <christophe.lyon@linaro.org>,  Thomas Preudhomme <thomas.preudhomme@linaro.org>,  "gcc-patches\@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] [RFC] PR target/52813 and target/11807
References: <DB7PR07MB53537B024F807B2F383C87B0E4A30@DB7PR07MB5353.eurprd07.prod.outlook.com>	<85840089.MtehzfUrTt@tpdeb> <20190107092337.GM30353@tucnak>	<AM6PR07MB5608D7EC0B184E1B3FC17242E4890@AM6PR07MB5608.eurprd07.prod.outlook.com>	<87lg3vicg5.fsf@arm.com> <20190110132111.GZ14180@gate.crashing.org>	<87zhs84374.fsf@arm.com> <20190111121814.GG14180@gate.crashing.org>
Date: Fri, 11 Jan 2019 12:23:00 -0000
In-Reply-To: <20190111121814.GG14180@gate.crashing.org> (Segher Boessenkool's	message of "Fri, 11 Jan 2019 06:18:14 -0600")
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Segher Boessenkool <segher@kernel.crashing.org> writes:
>> I think it would act like a noreturn call to an unknown function.
>
> Except it won't behave like a call otherwise (on Power all calls force a
> stack frame, for example; and on all targets noreturn calls do the same
> currently I think?)

I agree no current asm would behave like a call (e.g. causing leaf_p
to be false, and more).  The point of adding the attribute would be to
change that.

Richard