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Date:   Fri, 16 Jan 2015 15:47:04 +0100
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Daniel Sanders <daniel.sanders@imgtec.com>
Cc:     linux-mips@linux-mips.org, Paul Burton <paul.burton@imgtec.com>,
        Markos Chandras <markos.chandras@imgtec.com>,
        James Hogan <james.hogan@imgtec.com>,
        Behan Webster <behanw@converseincode.com>,
        Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>,
        David Daney <ddaney.cavm@gmail.com>
Subject: Re: [PATCH v2] MIPS: Changed current_thread_info() to an equivalent
 supported by both clang and GCC
Message-ID: <20150116144703.GC22296@linux-mips.org>
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On Sat, Jan 10, 2015 at 12:52:40PM +0000, Daniel Sanders wrote:

> The problem is that clang doesn't honour named registers on local variables
> and silently treats them as normal uninitialized variables. However, it
> does honour them on global variables.

Older versions of <asm/unistd.h> which have been copied into some userland
packages are using some local register variables in syscall wrappers.  These
syscall wrappers have historically been a pain because every once in a
while they got broken by a new GCC release or other issues.  If you're
lucky that has been resolved by the maintainers of those external software
packages - the only way to be certain is the review ...

At least the kernel does no longer do syscalls.

  Ralf