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From: "krzysztof.a.nowicki+gcc at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/95052] Excess padding of partially initialized strings/char arrays
Date: Mon, 11 May 2020 13:07:04 +0000	[thread overview]
Message-ID: <bug-95052-4-vtkKjVlten@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-95052-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95052

--- Comment #2 from Krzysztof Nowicki <krzysztof.a.nowicki+gcc at gmail dot com> ---
(In reply to Richard Biener from comment #1)
> I'm not sure what you describe as padding is padding.  Instead it's valid to
> access all elements of the array you declare and thus it must be initialized.

Not in this case, as this is a constant initializer, which is anonymous and is
never accessible from the code directly.

> What could be done is elide zero-padding parts to a memset() call.

Exactly, this is what I mean. Currently this actually happens in the generated
code (see attachment), but the part of GCC which allocates the variable in the
.rodata section doesn't know that and allocates memory for the full contents
including the zero padding.

  parent reply	other threads:[~2020-05-11 13:07 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-11 10:50 [Bug c/95052] New: " krzysztof.a.nowicki+gcc at gmail dot com
2020-05-11 11:32 ` [Bug c/95052] " rguenth at gcc dot gnu.org
2020-05-11 13:07 ` krzysztof.a.nowicki+gcc at gmail dot com [this message]
2020-05-11 13:18 ` krzysztof.a.nowicki+gcc at gmail dot com
2020-05-11 14:41 ` [Bug target/95052] " msebor at gcc dot gnu.org
2020-05-11 14:51 ` krzysztof.a.nowicki+gcc at gmail dot com
2020-05-11 19:06 ` [Bug middle-end/95052] " jakub at gcc dot gnu.org
2020-05-13  5:05 ` krzysztof.a.nowicki+gcc at gmail dot com
2020-05-13 12:33 ` [Bug middle-end/95052] [9/10/11 Regression] " pinskia at gcc dot gnu.org
2020-05-29  8:43 ` cvs-commit at gcc dot gnu.org
2020-05-29 13:27 ` mkuvyrkov at gcc dot gnu.org
2020-05-29 14:22 ` mkuvyrkov at gcc dot gnu.org
2020-05-29 14:26 ` mkuvyrkov at gcc dot gnu.org
2020-05-29 19:37 ` jakub at gcc dot gnu.org
2020-05-31  9:55 ` cvs-commit at gcc dot gnu.org
2020-08-03 11:10 ` ptsneves at gmail dot com
2021-01-14  8:46 ` [Bug middle-end/95052] [9/10 " rguenth at gcc dot gnu.org
2021-06-01  8:17 ` rguenth at gcc dot gnu.org
2022-05-27  9:42 ` [Bug middle-end/95052] [10 " rguenth at gcc dot gnu.org
2022-06-28 10:40 ` jakub at gcc dot gnu.org
2023-07-07  8:52 ` rguenth at gcc dot gnu.org

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