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From: "tsqurt at outlook dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libcc1/113977] debug info for alignment of structure is
 unspecified
Date: Sun, 18 Feb 2024 02:41:15 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113977

--- Comment #4 from Tan Senqi <tsqurt at outlook dot com> ---
(In reply to Andrew Pinski from comment #3)
> For me with the trunk GCC we get:
> ```
> (gdb) expr z[0]._[0] =3D 1
> gdb command line:1:1: error: size of array element is not a multiple of i=
ts
> alignment
> Compilation failed.
> (gdb) expr y[0]._[0] =3D 1
> (gdb) expr x[0]._[0] =3D 1
> gdb command line:1:1: error: alignment of array elements is greater than
> element size
> Compilation failed.
>=20
> ```
>=20
> I am starting to think this is a gdb issue ...

I think gcc can generate a DW_AT_alignment for my struct to solve this prob=
lem.
But why the alignment is considered as 8, I am not sure about this. If it is
inherited from the default structure alignment requirement on the platform,
then gcc should specify alignment for those whose alignment is not 8. Or 8 =
is
not the default value by DWARF5(i.e. undefined), then it is surely a bug in
gdb.=