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From: "george.thopas at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/100804] storage order swapped with specific opt
Date: Thu, 27 May 2021 21:38:13 +0000	[thread overview]
Message-ID: <bug-100804-4-iiiNgQ5mPu@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-100804-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100804

--- Comment #2 from George Thopas <george.thopas at gmail dot com> ---
After looking at the updated documentation and trying the an update kernel with
warning it still leaves some things open. 

The updated documentation says:

"Moreover, the use of type punning or aliasing to toggle the storage order
is not supported; that is to say, if a given scalar object can be accessed
through distinct types that assign a different storage order to it, then the
behaviour is undefined"

- In my example the new warning fires on a struct only having chars. I don't
see how that is applicable here or how a char array could have a different
storage
order in either big or little endian.  

- Regardless of that fact. That field is also never accessed in my example code 
Al 2 fields of the structs actually read are consistently be (in)
and the one written is (out) le.  The ones compare are of the same type. 

Thanks again

  parent reply	other threads:[~2021-05-27 21:38 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-27 18:23 [Bug c/100804] New: " george.thopas at gmail dot com
2021-05-27 19:29 ` [Bug c/100804] " pinskia at gcc dot gnu.org
2021-05-27 21:38 ` george.thopas at gmail dot com [this message]
2021-05-27 23:16 ` ebotcazou at gcc dot gnu.org

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