From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1944) id 5BB13385E004; Wed, 14 Feb 2024 15:06:53 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5BB13385E004 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1707923213; bh=cGCGLEzkVj1KajsJl1w/iba01koA31pI2uJJ5SBXmS8=; h=From:To:Subject:Date:From; b=USE0BAQBeZjfDEKkTeV9YwOcFD9yFxSv8VA8RJEW2l/C481ONZ75N5fRh0ARHZuMF QZUWVlxCdkBHEC4mjtxBxuYmq2QY3FW+KiajnQCjFxPvWyjYMf0tPO8oFLN9sr+Y8X KYDYR6Y9R60akBSlcyhRk8+kPc3wlXs0+/Efl3aY= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Szabolcs Nagy To: glibc-cvs@sourceware.org Subject: [glibc/arm/gcs] aarch64: mark swapcontext with indirect_return X-Act-Checkin: glibc X-Git-Author: Szabolcs Nagy X-Git-Refname: refs/heads/arm/gcs X-Git-Oldrev: 996a31b2a3313039b5c66d7de15577e5bc145278 X-Git-Newrev: 99f884d57f17afea877006284f469747711e1d51 Message-Id: <20240214150653.5BB13385E004@sourceware.org> Date: Wed, 14 Feb 2024 15:06:53 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=99f884d57f17afea877006284f469747711e1d51 commit 99f884d57f17afea877006284f469747711e1d51 Author: Szabolcs Nagy Date: Thu Dec 28 15:53:38 2023 +0000 aarch64: mark swapcontext with indirect_return Diff: --- sysdeps/aarch64/bits/indirect-return.h | 36 ++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/sysdeps/aarch64/bits/indirect-return.h b/sysdeps/aarch64/bits/indirect-return.h new file mode 100644 index 0000000000..99905f21fa --- /dev/null +++ b/sysdeps/aarch64/bits/indirect-return.h @@ -0,0 +1,36 @@ +/* Definition of __INDIRECT_RETURN. AArch64 version. + Copyright (C) 2024 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _UCONTEXT_H +# error "Never include directly; use instead." +#endif + +/* __INDIRECT_RETURN indicates that swapcontext may return via + an indirect branch. This happens when GCS is enabled, so + add the attribute if available, otherwise returns_twice has + a similar effect, but it prevents some code transformations + that can cause build failures in some rare cases so it is + only used when GCS is enabled. */ +#if __glibc_has_attribute (__indirect_return__) +# define __INDIRECT_RETURN __attribute__ ((__indirect_return__)) +#elif __glibc_has_attribute (__returns_twice__) \ + && defined __ARM_FEATURE_GCS_DEFAULT +# define __INDIRECT_RETURN __attribute__ ((__returns_twice__)) +#else +# define __INDIRECT_RETURN +#endif