Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20221114114344.18650-1-jirislaby@kernel.org> <20221114114344.18650-38-jirislaby@kernel.org>
In-Reply-To: <20221114114344.18650-38-jirislaby@kernel.org>
From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Mon, 14 Nov 2022 18:01:10 +0100
Message-ID: <CANiq72nWnFpC5JWv7Z1Fmg9vLoQoMbGG+wwFJm0GW81Pw0Me2w@mail.gmail.com>
Subject: Re: [PATCH 37/46] Compiler attributes, lto: disable __flatten with LTO
To:     "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Andi Kleen <andi@firstfloor.org>,
        Miguel Ojeda <ojeda@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Martin Liska <mliska@suse.cz>, Jiri Slaby <jslaby@suse.cz>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Nov 14, 2022 at 12:45 PM Jiri Slaby (SUSE) <jirislaby@kernel.org> wrote:
>
> +#ifndef CONFIG_LTO_GCC
>  # define __flatten                     __attribute__((flatten))
> +#else
> +/* Causes very large memory use with gcc in LTO mode */
> +# define __flatten
> +#endif

Currently, this header avoids attributes that depend on configuration
options on purpose (see the comment at the top), so it would be best
to move it elsewhere, e.g. `compiler_types.h`.

Though I feel bad about having to move this attribute out since it is
just that config option compared to other more involved bits in
`compiler_types.h`... :(

Cheers,
Miguel