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From: Yubin Ruan <ablacktshirt@gmail.com>
To: ccan@lists.ozlabs.org
Subject: useless expression in typesaft_cb_cast
Date: Mon, 12 Mar 2018 04:05:27 +0800	[thread overview]
Message-ID: <20180311200527.GF6146@HP> (raw)

Hi,

typesaft_cb_cast() is defined in typesaft_cb.h as:

    #define typesafe_cb_cast(desttype, oktype, expr)                  \
    	__builtin_choose_expr(                                        \
    		__builtin_types_compatible_p(__typeof__(0?(expr):(expr)), \
    					     oktype),                                 \
    		(desttype)(expr), (expr))

what is the point of that "0?(expr):(expr)" ?

Yubin
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             reply	other threads:[~2018-03-11 20:05 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-11 20:05 Yubin Ruan [this message]
2018-03-13  9:49 ` useless expression in typesaft_cb_cast Rusty Russell

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