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From: "vt at altlinux dot org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug middle-end/106470] Subscribed access to __m256i casted to
 (uint16_t *) produces garbage or a warning
Date: Thu, 28 Jul 2022 22:16:59 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106470

--- Comment #5 from Vitaly Chikunov <vt at altlinux dot org> ---
I experimented with `_mm256_extract_epi16` too and loop liek this worked to=
o:

```
# pragma GCC unroll 16
        for (size_t i =3D 0; i < 16; i++) {
                printf(" %04x", _mm256_extract_epi16(tmp, i));
        }
```

That's why I started to experiment with `#pragma GCC unroll 16` for the 2nd
test case.

Curiously, in `liboqs` adding the pragma removes the `=E2=80=98tmp=E2=80=99=
 is used
uninitialized` warning (while w/o pragma it compiles with warning), but in
reproducer it acts contrary - with the pragma it causes warning and w/o pra=
gma
it compiles quietly.=