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From: Peter Maydell <peter.maydell@linaro.org>
Date: Mon, 11 May 2015 11:43:10 +0100
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Subject: Re: [Qemu-devel] [RFC PATCH 02/34] tcg+qom: QOMify core CPU
	defintions
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To: Peter Crosthwaite <crosthwaitepeter@gmail.com>
Cc: Edgar Iglesias <edgari@xilinx.com>, Soren Brinkmann <sorenb@xilinx.com>, QEMU Developers <qemu-devel@nongnu.org>, =?UTF-8?Q?Andreas_F=C3=A4rber?= <afaerber@suse.de>, Richard Henderson <rth@twiddle.net>

On 11 May 2015 at 07:29, Peter Crosthwaite <crosthwaitepeter@gmail.com> wrote:
> These definitions are defined per-target and globall linked/defined
> between core code and target-foo. QOMify them. Provide weakly linked
> conditional default implementations for the non-qomified global fns.
> This means converted architectures which install a QOM hook do not need
> to define a function for the old globals even the common code expects
> to link against something.
>
> +void __attribute__((weak)) gen_intermediate_code(CPUArchState *env,
> +                                                 struct TranslationBlock *tb)
> +{
> +    abort();
> +}

__attribute__((weak)) doesn't work on all the platforms we need
to support, I'm afraid. The approach we've settled on instead
is to provide stub functions in source files in the stubs/ directory
which get built into a libqemustub.a library; then the linker will
fish out the .o files from that as needed to satisfy otherwise
missing symbols.

-- PMM