RE: [PATCH 2/5] arm64: add __READ_ONCE_EX()

[David Laight]

From: Haris Okanovic
> Sent: 05 November 2024 18:31
> 
> Perform an exclusive load, which atomically loads a word and arms the
> exclusive monitor to enable wfet()/wfe() accelerated polling.
> 
...
> +	atomic ? (typeof(*__x))__u.__val : (*(volatile typeof(__x))__x);\

That doesn't do what you want it to do.
(It is wrong in READ_ONCE() as well.)

?: is treated like an arithmetic operator and the result will get
promoted to 'int'.
Moving the first cast outside the ?: probably works:
	(typeof(*__x))(atomic ? __u.__val : (*(volatile typeof(__x))__x));

   David

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