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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Florian Weimer' <fweimer@redhat.com>,
        Lukas Wunner <lukas@wunner.de>
CC:     Linus Torvalds <torvalds@linux-foundation.org>,
        Will Deacon <will@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Arnd Bergmann <arnd@kernel.org>,
        Russell King - ARM Linux admin <linux@armlinux.org.uk>,
        "linux-toolchains@vger.kernel.org" <linux-toolchains@vger.kernel.org>,
        "Mark Rutland" <mark.rutland@arm.com>,
        Theodore Ts'o <tytso@mit.edu>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        Ext4 Developers List <linux-ext4@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: RE: Aarch64 EXT4FS inode checksum failures - seems to be weak memory
 ordering issues
Thread-Topic: Aarch64 EXT4FS inode checksum failures - seems to be weak memory
 ordering issues
Thread-Index: AQHW6OeTm0FM5rtghkqQZIJPrgzUmKokAGNg
Date:   Tue, 12 Jan 2021 13:46:16 +0000
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From: Florian Weimer
> Sent: 12 January 2021 13:32
> 
> * Lukas Wunner:
> 
> > On Fri, Jan 08, 2021 at 12:02:53PM -0800, Linus Torvalds wrote:
> >> I appreciate Arnd pointing out "--std=gnu11", though. What are the
> >> actual relevant language improvements?
> >>
> >> Variable declarations in for-loops is the only one I can think of. I
> >> think that would clean up some code (and some macros), but might not
> >> be compelling on its own.
> >
> > Anonymous structs/unions.  I used to have a use case for that in
> > struct efi_dev_path in include/linux/efi.h, but Ard Biesheuvel
> > refactored it in a gnu89-compatible way for v5.7 with db8952e7094f.
> 
> Aren't those a GNU extension supported since GCC 3.0?

They are certainly pretty old.
The 15 year old gcc we use for release builds (so binaries work
on old distributions) supports them.

	David

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