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From: Wilhelm Meier <wilhelm.meier@hs-kl.de>
To: <gcc-help@gcc.gnu.org>
Subject: Unions, common-initial subsequence and UB
Date: Thu, 20 Oct 2022 13:46:52 +0200	[thread overview]
Message-ID: <8dc1aaa8-fe1b-e11b-b5e4-ae1acc30ff02@hs-kl.de> (raw)

Hi all,

this is more a general question instead of a g++ specific one:

the standard explicitly makes this exception: accessing an inactive 
union member is not UB if the members are structs with initial common 
sequence.

Is this also true in a constexpr context? I ask this because the chapter 
for constexpr expression does not mention this exception accessing an 
inactive memeber.

Thanks for hints,
  Wilhelm

             reply	other threads:[~2022-10-20 11:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-20 11:46 Wilhelm Meier [this message]
2022-10-20 13:10 ` Wilhelm Meier

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