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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/108342] std::complex: ignoring packed attribute because of
 unpacked non-POD field
Date: Mon, 09 Jan 2023 16:31:46 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108342

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #5)
> I don't know whether clang allows packing non-PODs, or just doesn't ever
> warn for them, or has a special case for std::complex, or does something
> smarter like not warn for types that have no padding bytes anyway (so that
> packing them would be a no-op).

clang allows packing of non-PODs:
```
class f
{
public:
  f();
private:
  int t[2];
};

typedef struct __attribute__((__packed__))
{
    /** Every frame starts with BB_FRAME_MAGIC. */
    unsigned magic;
    unsigned char t;

    f bb_iq_samples[100];

} bb_frame_t;
```=