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References: <20181124235553.17371-1-cota@braap.org>
	<20181124235553.17371-8-cota@braap.org> <87h8ft3295.fsf@linaro.org>
From: Richard Henderson <richard.henderson@linaro.org>
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Date: Tue, 4 Dec 2018 07:33:01 -0600
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Subject: Re: [Qemu-devel] [PATCH v6 07/13] fpu: introduce hardfloat
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To: =?UTF-8?Q?Alex_Benn=c3=a9e?= <alex.bennee@linaro.org>, "Emilio G. Cota" <cota@braap.org>
Cc: qemu-devel@nongnu.org

On 12/4/18 6:28 AM, Alex Bennée wrote:
> Emilio G. Cota <cota@braap.org> writes:
>> This assumes that QEMU is running on an IEEE754-compliant FPU and
>> that the rounding is set to the default (to nearest). The
>> implementation-dependent specifics of the FPU should not matter; things
>> like tininess detection and snan representation are still dealt with in
>> soft-fp. However, this approach will break on most hosts if we compile
>> QEMU with flags such as -ffast-math. We control the flags so this should
>> be easy to enforce though.
> 
> We don't currently enforce this though although maybe that would be too
> much hand holding for compiler ricers hell bent on not understanding the
> flags they use.

We could always

#ifdef __FAST_MATH__
#error "Silliness like this will get you nowhere"
#endif


r~