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Re: [PATCH] Support for known unknown alignment


On 20 April 2012 16:54, Martin Jambor <mjambor@suse.cz> wrote:
> two days ago I talked to Richi on IRC about the functions to determine
> the expected alignment of objects and pointers we have and he
> suggested that get_object_alignment_1 and get_pointer_alignment_1
> should return whether the alignment is actually known

Can you explain how returning "unknown" is different from returning
some minimal known alignment? Comments like:

> ! /* Compute values M and N such that M divides (address of EXP - N) and
> ! Â Âsuch that N < M. ÂStore N in *BITPOSP and return M.

suggest that M=1, N=0 is always a valid conservative thing to return.

If there is a difference, the comment should explain what it means.

Thanks,
Jay.


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