RE: [PATCH] workqueue: fix enum type for gcc-13

[David Laight]

From: Arnd Bergmann
> Sent: 17 January 2023 16:41
> 
> In gcc-13, the WORK_STRUCT_WQ_DATA_MASK constant is a signed 64-bit
> type on 32-bit architectures because the enum definition has both
> negative numbers and numbers above LONG_MAX in it:
> 
...
>  	/* convenience constants */
>  	WORK_STRUCT_FLAG_MASK	= (1UL << WORK_STRUCT_FLAG_BITS) - 1,
> -	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
> +	WORK_STRUCT_WQ_DATA_MASK = (unsigned long)~WORK_STRUCT_FLAG_MASK,
>  	WORK_STRUCT_NO_POOL	= (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,

How can that make any difference?
You aren't changing the value or type (which makes no difference)
of WORK_STRUCT_WQ_DATA_MASK.
Indeed you require it to have the high bit set.

So if the enum contains a -1 somewhere gcc-13 will promote
everything to s64.

Either declare gcc-13 as 'BROKEN' or change the:
	return (void *)(data & WORK_STRUCT_WQ_DATA_MASK);
to
	return (void *)(data & ~WORK_STRUCT_FLAG_MASK);

or use #defines.

	David

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