[PATCH] Make cstddef / cstdarg more robust (PR 69881)

[Jonathan Wakely]

On 23/02/16 11:09 +0100, Jakub Jelinek wrote:
>On Tue, Feb 23, 2016 at 10:00:58AM +0000, Bernd Edlinger wrote:
>> Previously the g++ default was --std=gnu++98,
>> but gcc-6 changed the default to --std=gnu++14.
>>
>> And when building gcc-4.9, stage1 does not override that with
>> --std=gnu++98.
>>
>> That has changed, and that triggers the latent bug.
>
>So just use -std=gnu++98 in STAGE1_CXXFLAGS or configure with
>CXX='g++ -std=gnu++98' if you try to build gcc-4.9 with gcc 6?
>
>I really don't think we should work around this in GCC 6.

I agree, but #undefining those macros doesn't hurt, and hopefully the
issue will go away.