[Bug c++/114928] New: #pragma packed(push,1) should give the same warning as __attribute__((packed))

[Bug c++/114928] New: #pragma packed(push,1) should give the same warning as __attribute__((packed))

[dhylands at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114928

            Bug ID: 114928
           Summary: #pragma packed(push,1) should give the same warning as
                    __attribute__((packed))
           Product: gcc
           Version: 13.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dhylands at gmail dot com
  Target Milestone: ---

Created attachment 58091
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58091&action=edit
File that compiles with no warnings

I'm using the ARM Toolchain
arm-gnu-toolchain-13.2.Rel1-x86_64-aarch64-none-linux-gnu/bin/aarch64-none-linux-gnu-g++

running on Ubuntu 20.04

If I delcare my structure using:

struct Foo {
    char y;
    int x;
} __attribute__((packed));

then the compiler correctly gives me a warning about taking the address of a
packed member:

warning: taking address of packed member of ‘Foo’ may result in an unaligned
pointer value [-Waddress-of-packed-member]

However, if I change the structure to use #pragma pack(push, 1) 

#pragma pack(push, 1)
struct Foo {
    char y;
    int x;
};
#pragma pack(pop)

then I don't get the warning (and my bug is that it should give the same
warning).

In either case the member offsets and structure size are the same.

[Bug c++/114928] #pragma packed(push,1) should give the same warning as __attribute__((packed))

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114928

Eric Gallager <egallager at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |egallager at gcc dot gnu.org
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=60972

--- Comment #1 from Eric Gallager <egallager at gcc dot gnu.org> ---
There are a number of other bugs open regarding inconsistencies between #pragma
pack and __attribute__((packed)); see for instance bug 60972 and related bugs
(not sure if this is a dup or even fully related, but it's at least worth
putting under "See Also"...)