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References: <20180203153935.8056-1-pbonzini@redhat.com>
	<20180203153935.8056-3-pbonzini@redhat.com>
From: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <2e6460d8-115a-9cbc-c77d-655a9e843abc@linaro.org>
Date: Sat, 3 Feb 2018 12:44:20 -0800
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Subject: Re: [Qemu-devel] [PATCH 2/5] lockable: add QemuLockable
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To: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org
Cc: famz@redhat.com, qemu-block@nongnu.org, stefanha@redhat.com

On 02/03/2018 07:39 AM, Paolo Bonzini wrote:
> +/* This function gives an error if an invalid, non-NULL pointer type is passed
> + * to QEMU_MAKE_LOCKABLE.  For optimized builds, we can rely on dead-code elimination
> + * from the compiler, and give the errors already at link time.
> + */
> +#ifdef __OPTIMIZE__
> +void unknown_lock_type(void *);
> +#else
> +static inline void unknown_lock_type(void *unused)
> +{
> +    abort();
> +}

Since you're using __builtin_choose_expr, I'm surprised you would need to test
__OPTIMZE__.  The nature of the builtin is such that it *must* eliminate the
other branch; otherwise the types don't even match up.

It might be worth using __attribute__((error("message"))) on the function too.

Otherwise,

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~