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Date: Thu, 2 May 2013 12:13:51 +0200
From: Szabolcs Nagy <>
Subject: Re: sign (in)consistency between architectures

* Jens Gustedt <> [2013-05-02 10:12:39 +0200]:
> I would prefer to have both worlds by using uint64_t (or directly the
> underlying base type) uniformly. There is no reason to have it signed:

yes probably that's the best solution

but note that even that can hurt: i've seen code like

  t = (double)clock();

(eg the time module in python does this) where interesting
low bits may get lost if clock_t is uint64_t

this might be common because clock_t is permitted to be
a floating-point type

of course this should not be a problem if the cast is
applied to the difference only
(other than uint64->double conversion is usually much
slower than int32->double conversion)
..but this issue is present on 64bit platforms anyway

siginfo is affected as well: clock_t is used in the union
in it which i think is aligned with glibc now

but i'm not against the uint64_t solution if we decide
breaking glibc abi here is ok

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