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From: "chenglulu at loongson dot cn" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug target/105514] rv64 qsort gets wrong result when '-O2 -DDEBUG'.
Date: Mon, 09 May 2022 01:19:30 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105514

--- Comment #2 from chenglulu <chenglulu at loongson dot cn> ---
(In reply to Andrew Pinski from comment #1)
> Just looking at the code, there seems to be some aliasing violations going
> on which is causing the problem.
>=20
> Sometimes accessing via unsigned long and others by double.
>=20
> Does -fno-strict-aliasing fixes the issue?

After adding the compile option '-fno-strict-aliasing', the program runs
without problems.

But I don't understand why one print affects so much?

Thanks!=