From: Eric Biggers <ebiggers3@gmail.com>
Subject: Re: [PATCH v7 0/5] Update LZ4 compressor module
Date: Wed, 8 Feb 2017 21:24:25 -0800
Message-ID: <20170209052425.GA4678@zzz>
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Cc: Sven Schmidt <4sschmid@informatik.uni-hamburg.de>,
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To: Minchan Kim <minchan@kernel.org>
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Also I noticed another bug, this time in LZ4_count():

> #if defined(CONFIG_64BIT)
> #define LZ4_ARCH64 1
> #else
> #define LZ4_ARCH64 0
> #endif
...
> #ifdef LZ4_ARCH64
>        if ((pIn < (pInLimit-3))
>                && (LZ4_read32(pMatch) == LZ4_read32(pIn))) {
>                pIn += 4; pMatch += 4;
>        }
> #endif

Because of how LZ4_ARCH64 is defined, it needs to be '#if LZ4_ARCH64'.

But I also think the way upstream LZ4 does 64-bit detection could have just been
left as-is; it has a function which gets inlined:

	static unsigned LZ4_64bits(void) { return sizeof(void*)==8; }

Eric