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From: "glaubitz at physik dot fu-berlin.de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/107498] Wrong optimization leads to unaligned access
 when compiling OpenLDAP
Date: Tue, 01 Nov 2022 21:53:29 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107498

--- Comment #6 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-be=
rlin.de> ---
(In reply to Eric Botcazou from comment #5)
> Note that the fields are marked volatile in the source:
>=20
>  union {
>   struct {
>    volatile indx_t pb_lower;
>    volatile indx_t pb_upper;
>   } pb;
>   uint32_t pb_pages;
>  } mp_pb;

My bad. I actually modified the source to see whether marking them "volatil=
e"
would alleviate the issue as suggested by Howard in the OpenLDAP bug report.

I'll attach the preprocessed source again, this time from the unmodified
=C2=BBmdb.c=C2=AB.=