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From: Zack Weinberg <zackw@panix.com>
Date: Fri, 1 May 2020 10:07:06 -0400
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Subject: Re: [PATCH 08/12] Rewrite abi-note.S in C.
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: GNU C Library <libc-alpha@sourceware.org>,
 Sudakshina Das <Sudi.Das@arm.com>
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On Fri, May 1, 2020 at 5:24 AM Szabolcs Nagy <szabolcs.nagy@arm.com> wrote:
> what about
>
> /* Note: Custom type is used as ElfW(Nhdr) is wrong on 64 bit targets.  */
>
> __attribute__((used, aligned(4), section(".note.ABI-tag")))
> static const struct
> {
>   int32_t namesz;
>   int32_t descsz;
>   int32_t type;
>   char name[4];
>   int32_t desc[4];
> } __abi_tag = {
>   4,   /* name length: 4  */
>   16,  /* data length: 4 32-bit numbers */
>   1,
>   "GNU",
>   { __ABI_TAG_OS, __ABI_TAG_VERSION }
> };
>
> this fixes the alignment, makes the symbol local, does not need
> endian.h and uses identifiers according to the gabi specification.

Looks good to me.  Fixing the array length means the compiler should
complain if __ABI_TAG_VERSION ever expands to the wrong number of
initializers.

zw