GMP 6.1.2 t-count_zeros failure on ARM with assertions

Marc Glisse marc.glisse at
Wed Dec 27 17:10:27 UTC 2017

On Wed, 27 Dec 2017, Niels Möller wrote:

> nisse at (Niels Möller) writes:
>> Pushed now.
> And below, a patch to delete all mention of COUNT_LEADING_ZEROS_0,
> except for tune/, which I'm not familiar with. What do you think?

It seems a bit sad to drop this information, in case we want to use it in 
the future, or if we want to share the file longlong.h with other 

As far as I understand, the issue was an inconsistency between using gcc's 
__builtin_clz (instead of some intrinsic or inline asm for the CLZ 
instruction) and still defining the macro COUNT_LEADING_ZEROS_0 to 32. I 
am not sure that warrants removing all COUNT_LEADING_ZEROS_0 everywhere.

But if we aren't using it at all, I don't have a very strong opinion.

Marc Glisse

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