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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103882] Register corruption in ASM only functions when optization is -O2/-Os/-O3
Date: Sat, 01 Jan 2022 20:34:12 +0000	[thread overview]
Message-ID: <bug-103882-4-pNL0g6TlVJ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103882-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103882

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
That is solely because you didn't write anything else in the function, try to
put some code around the inline asm and you'll see how it will misbehave even
with noipa attribute.
Your code is invalid as documented in GCC documentation, the behavior is
undefined, it can do anything, break with different optimization levels,
different compiler versions or revisions, it can appear to work in some cases
the way you intended, but it is still broken.

  parent reply	other threads:[~2022-01-01 20:34 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-31 17:11 [Bug target/103882] New: " krystalgamer at protonmail dot com
2021-12-31 18:53 ` [Bug target/103882] " pinskia at gcc dot gnu.org
2021-12-31 20:48 ` krystalgamer at protonmail dot com
2021-12-31 20:51 ` pinskia at gcc dot gnu.org
2021-12-31 20:51 ` pinskia at gcc dot gnu.org
2021-12-31 22:36 ` jakub at gcc dot gnu.org
2022-01-01 12:45 ` krystalgamer at protonmail dot com
2022-01-01 14:05 ` jakub at gcc dot gnu.org
2022-01-01 14:11 ` jakub at gcc dot gnu.org
2022-01-01 15:06 ` krystalgamer at protonmail dot com
2022-01-01 16:37 ` jakub at gcc dot gnu.org
2022-01-01 19:19 ` krystalgamer at protonmail dot com
2022-01-01 19:47 ` schwab@linux-m68k.org
2022-01-01 20:34 ` jakub at gcc dot gnu.org [this message]
2022-01-01 23:15 ` krystalgamer at protonmail dot com
2022-01-02 13:27 ` jakub at gcc dot gnu.org
2022-01-02 14:40 ` krystalgamer at protonmail dot com
2022-01-02 15:00 ` schwab@linux-m68k.org

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