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Date: Wed, 1 Jul 2020 20:50:26 +0200
From: Markus Wichmann <nullplan@gmx.net>
To: musl@lists.openwall.com
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Subject: [musl] Superfluous shift in qsort()?

Hi all,

I noticed something while reading code today: Near the end of qsort(),
we have this gem:

shl(p, 2);
pshift -= 2;
p[0] ^= 7;
shr(p, 1);

Now, I don't know if I am missing something, but don't the shl and the
shr partially cancel out? Isn't this the same as

shl(p, 1);
p[0] ^= 3;

As it is, it isn't wrong, just weird.

Ciao,
Markus