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Subject: Re: [PATCH] kvm/emulate: fix a -Werror=cast-function-type
To:     Qian Cai <cai@lca.pw>, Jim Mattson <jmattson@google.com>
Cc:     Sean Christopherson <sean.j.christopherson@intel.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Joerg Roedel <joro@8bytes.org>, kvm list <kvm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <28680b99-d043-ee02-dab3-b5ce8c2e625b@redhat.com>
Date:   Fri, 14 Feb 2020 20:33:50 +0100
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On 14/02/20 20:14, Qian Cai wrote:
>> It seems misguided to define a local variable just to get an implicit
>> cast from (void *) to (fastop_t). Sean's first suggestion gives you
>> the same implicit cast without the local variable. The second
>> suggestion makes both casts explicit.
> 
> OK, I'll do a v2 using the first suggestion which looks simpler once it passed
> compilations.
> 

Another interesting possibility is to use an unnamed union of a
(*execute) function pointer and a (*fastop) function pointer.

Paolo