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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/106503] "const char []" in local scope never initialized
Date: Tue, 02 Aug 2022 10:01:41 +0000	[thread overview]
Message-ID: <bug-106503-4-XPb00mPZGX@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-106503-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106503

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #5)
> Your program has undefined behaviour, that means the WHOLE program,
> including inside that block.

Or in the case where you copy the pointer, and then overwrite it with another
value, that isn't undefined, but the value is not used. The point of
optimization is to remove unnecessary code, like setting bytes in memory that
will never get read back again.

If the contents of junk are not needed, why waste cycles initializing those
bytes?

      parent reply	other threads:[~2022-08-02 10:01 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-08-02  7:31 [Bug c/106503] New: " eb at emlix dot com
2022-08-02  7:36 ` [Bug c/106503] " eb at emlix dot com
2022-08-02  7:37 ` pinskia at gcc dot gnu.org
2022-08-02  7:47 ` pinskia at gcc dot gnu.org
2022-08-02  9:08 ` eb at emlix dot com
2022-08-02  9:44 ` redi at gcc dot gnu.org
2022-08-02 10:01 ` redi at gcc dot gnu.org [this message]

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