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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: Andreas Schwab <schwab@linux-m68k.org>
Cc: Po Lu <luangruo@yahoo.com>,  Eli Zaretskii <eliz@gnu.org>,
	emacs-devel@gnu.org
Subject: Re: Compiler warnings in dispnew.c
Date: Mon, 29 Nov 2021 12:49:56 -0500	[thread overview]
Message-ID: <jwvmtlm6ej5.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <87wnksfsiy.fsf@linux-m68k.org> (Andreas Schwab's message of "Sun, 28 Nov 2021 12:07:01 +0100")

Andreas Schwab [2021-11-28 12:07:01] wrote:
> -  memcpy (&to->x, &from->x, sizeof *to - off);
> +  memcpy ((char *) to + off, (char *) from + off, sizeof *to - off);

I wonder: is the (char*) cast sufficient or is it necessary to
"obfuscate" the code by writing `to + off` instead of `&to->x`?
[ By "obfuscate" I mean here to hide from the compiler, rather than from
  humans, because I'm not sure which of the two is more clear to
  a human, here.  ]


        Stefan




  parent reply	other threads:[~2021-11-29 17:49 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <87fsrg7gdt.fsf.ref@yahoo.com>
2021-11-28  9:56 ` Compiler warnings in dispnew.c Po Lu
2021-11-28 10:48   ` Eli Zaretskii
2021-11-28 10:57     ` Andreas Schwab
2021-11-28 11:02     ` Po Lu
2021-11-28 11:07       ` Andreas Schwab
2021-11-28 15:29         ` Eli Zaretskii
2021-11-29  0:35           ` Po Lu
2021-11-29 17:49         ` Stefan Monnier [this message]
2021-11-29 17:53           ` Andreas Schwab
2021-11-28 11:03     ` Eli Zaretskii
2021-11-28 11:10       ` Andreas Schwab
2021-11-28 11:18         ` Eli Zaretskii
2021-11-28 11:44           ` Andreas Schwab
2021-11-28 11:11       ` Po Lu

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