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Date:   Sat, 5 Nov 2022 21:54:01 +0100
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Uros Bizjak <ubizjak@gmail.com>, x86@kernel.org,
        willy@infradead.org, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        aarcange@redhat.com, kirill.shutemov@linux.intel.com,
        jroedel@suse.de
Subject: Re: [PATCH 11/13] x86_64: Remove pointless set_64bit() usage
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On Sat, Nov 05, 2022 at 04:14:19PM +0100, Peter Zijlstra wrote:
> Also:
> 
> $ ./align
> 16, 16
> 
> ---
> 
> #include <stdio.h>
> 
> int main(int argx, char **argv)
> {
> 	__int128 a;
> 
> 	printf("%d, %d\n", sizeof(a), __alignof(a));
> 	return 0;
> }

zx2c4@thinkpad /tmp $ x86_64-linux-musl-gcc -O2 a.c -static && qemu-x86_64 ./a.out
16, 16
zx2c4@thinkpad /tmp $ aarch64-linux-musl-gcc -O2 a.c -static && qemu-aarch64 ./a.out
16, 16
zx2c4@thinkpad /tmp $ powerpc64le-linux-musl-gcc -O2 a.c -static && qemu-ppc64le ./a.out
16, 16
zx2c4@thinkpad /tmp $ s390x-linux-musl-gcc -O2 a.c -static && qemu-s390x ./a.out
16, 8
zx2c4@thinkpad /tmp $ riscv64-linux-musl-gcc -O2 a.c -static && qemu-riscv64 ./a.out
16, 16

Er, yea, you're right. Looks like of these, it's just s390x, so
whatever.

Jason