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Message-ID: <cd25bf28f13ab3fd438fbce1d3357939b637813e.camel@mengyan1223.wang>
Subject: Re: [PATCH] libstdc++: Implement std::unreachable() for C++23
 (P0627R6)
From: Xi Ruoyao <xry111@mengyan1223.wang>
To: Matthias Kretz <m.kretz@gsi.de>, gcc-patches@gcc.gnu.org, 
 libstdc++@gcc.gnu.org
Date: Thu, 31 Mar 2022 23:59:26 +0800
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References: <20220331153029.1898244-1-jwakely@redhat.com>
 <3572914.e9J7NaK4W3@minbar>
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On Thu, 2022-03-31 at 17:50 +0200, Matthias Kretz via Gcc-patches wrote:
> I like it. But I'd like it even more if we could have
>=20
> #elif defined _UBSAN
> =C2=A0=C2=A0=C2=A0 __ubsan_invoke_ub("reached std::unreachable()");
>=20
> But to my knowledge UBSAN has no hooks for the library like this
> (yet).

UBSAN can catch __builtin_unreachable() and print a message "execution
reached an unreachable program point".
--=20
Xi Ruoyao <xry111@mengyan1223.wang>
School of Aerospace Science and Technology, Xidian University