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Re: Do BLKmode bit-fields still exist?


> Isn't it enough to specify DECL_PACKED here?  The tree.h docs
> about DECL_BIT_FIELD are a bit unspecific compared to
> DECL_PACKED.
>
> /* Nonzero in a FIELD_DECL means it is a bit field, and must be
> accessed   specially.  */
>
> vs.
>
> /* In a FIELD_DECL, indicates this field should be bit-packed.  */
>
> where it seems, as your field isn't a bitfield, using DECL_PACKED
> looks more appropriate?

No, DECL_PACKED is an "input" flag for stor-layout.c, it isn't used in the 
middle-end (except in the recently added contains_packed_reference but this 
is wrong and should be fixed), the "output" flag that drives the middle-end 
is DECL_BIT_FIELD.  stor-layout.c attempts to clear the latter to improve the 
code, it never changes the former.

-- 
Eric Botcazou


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