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Subject: Re: [PATCH] Check endianess detection.
To: "H.J. Lu" <hjl.tools@gmail.com>,
 Richard Biener <richard.guenther@gmail.com>
Cc: Jakub Jelinek <jakub@redhat.com>, GCC Patches <gcc-patches@gcc.gnu.org>
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From: =?UTF-8?Q?Martin_Li=c5=a1ka?= <mliska@suse.cz>
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Date: Mon, 23 Mar 2020 18:17:20 +0100
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On 3/23/20 5:06 PM, H.J. Lu wrote:
> #if __has_include (<endian.h>)
> ...
> #ifdef __BYTE_ORDER
> #if __BYTE_ORDER == __BIG_ENDIAN
> ...
> 
> We support V2 interface only if <endian.h> defines __BYTE_ORDER?

Right now we rely on __BIG_ENDIAN__ which is a weak endianess detection.
So we either need a very robust endianess detection (as mention in this thread):
https://github.com/llvm-mirror/compiler-rt/blob/master/lib/builtins/int_endianness.h

or

we'll come up with ld_plugin_symbol_v2

or

we will shift values in 'int def' in order to support symbol_type and section_kind.

What do you prefer H.J.?
Thanks,
Martin