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Date:   Tue, 5 Oct 2021 21:06:36 +0200 (CEST)
From:   Jan Engelhardt <jengelh@inai.de>
To:     Steven Rostedt <rostedt@goodmis.org>
cc:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
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Subject: Re: [RFC][PATCH] rcu: Use typeof(p) instead of typeof(*p) *
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On Tuesday 2021-10-05 20:40, Steven Rostedt wrote:
>> 
>> >>>> typeof(*p) *________p1 = (typeof(*p) *__force)READ_ONCE(p);  
>> 
>> #define static_cast(type, expr) ((struct { type x; }){(expr)}.x)
>> typeof(p) p1 = (typeof(p) __force)static_cast(void *, READ_ONCE(p));
>> 
>> Let the name not fool you; it's absolutely _not_ the same as C++'s 
>> static_cast, but still: it does emit a warning when you do pass an 
>> integer, which is better than no warning at all in that case.
>> 
>>  *flies away*
>
>Are you suggesting I should continue this exercise ;-)

“After all, why not?”

typeof(p) p1 = (typeof(p) __force)READ_ONCE(p) +
               BUILD_BUG_ON_EXPR(__builtin_classify_type(p) != 5);