Messages in this thread | | | Date | Wed, 14 Feb 2024 20:39:35 +0300 | From | Alexey Dobriyan <> | Subject | Re: [RFC] include/linux/make_type.h: Helpers for making u16/u32/u64 values |
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On Wed, Feb 14, 2024 at 07:32:10PM +0200, Andy Shevchenko wrote: > On Wed, Feb 14, 2024 at 08:20:55PM +0300, Alexey Dobriyan wrote: > > ... > > > Secondly, > > > > #define make_u64(hi__, lo__) ((u64)(hi__) << 32 | (u32)(lo__)) > > > > doesn't truncate hi, why? > > Because it's not needed (the whole point AFAIU is to override promotion > to a _signed_ type (int) and here it makes no difference)?
Well,
make_u64((u64)-1, 0)
will return (u64)-1 unlike
make_u16((u64)-1, 0)
which will return 0xff00. BTW, I'm for truncation, but it should be done everywhere.
Thirdly, there were no users posted.
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