From: Eli Zaretskii <eliz@gnu.org>
To: luangruo@yahoo.com
Cc: emacs-devel@gnu.org
Subject: Re: Compiler warnings in dispnew.c
Date: Sun, 28 Nov 2021 13:03:48 +0200 [thread overview]
Message-ID: <83sfvgwnhn.fsf@gnu.org> (raw)
In-Reply-To: <83tufwwo7z.fsf@gnu.org> (message from Eli Zaretskii on Sun, 28 Nov 2021 12:48:00 +0200)
> Date: Sun, 28 Nov 2021 12:48:00 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: emacs-devel@gnu.org
>
> > From: Po Lu <luangruo@yahoo.com>
> > Date: Sun, 28 Nov 2021 17:56:30 +0800
> >
> > Building with checking, I get:
> >
> > CC dispnew.o
> > In function ‘copy_row_except_pointers’,
> > inlined from ‘assign_row’ at dispnew.c:1050:3,
> > inlined from ‘mirror_make_current’ at dispnew.c:2761:3:
> > dispnew.c:1037:3: warning: ‘memcpy’ offset [48, 255] from the object at ‘current_row’ is out of the bounds of referenced subobject ‘x’ with type ‘int’ at offset 44 [-Warray-bounds]
I don't understand the data the compiler prints, specifically why it
says "offset [48, 255]" and then "at offset 44".
If you put a breakpoint at line 2761 of mirror_make_current, and when it
breaks, type
(gdb) ptype /o current_row
(gdb) ptype /o desired_row
what do you see in offsets of x and in the total size of the
structure?
(Note: to hit the breakpoint, you need to invoke "emacs -Q -nw", the
"-nw" part is important.)
next prev parent reply other threads:[~2021-11-28 11:03 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
2021-11-29 17:53 ` Andreas Schwab
2021-11-28 11:03 ` Eli Zaretskii [this message]
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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