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From: "deller at gmx dot de" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/102162] Byte-wise access optimized away at
 -O1 and above
Date: Wed, 01 Sep 2021 21:15:30 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102162

--- Comment #6 from deller at gmx dot de ---
> So, it seems the __aligned__ attribute is ignored:
> extern u32 output_len __attribute__((__aligned__(1)));

I think the aligned attribute is not relevant here. Even
        u32 output_len;
will generate word-accesses.
I'd say that the "forcement-to-packed" is ignored
when the compiler knows that the source is aligned.
The "__attribute__((__packed__))" should *always* trigger byte-accesses.=