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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libstdc++/97311] Bug in std::seed_seq::generate() when integer
 type has more than 32 bits
Date: Wed, 07 Oct 2020 20:28:38 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D97311

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I don't see how manually written arithmetic with explicit % operations is g=
oing
to beat using built-in types that do that automatically.

If 64-bit arithmetic is faster than 32-bit arithmetic, I would expect the
compiler to use 64-bit registers and mask them off to produce 32-bit result=
s.
If the user has to do that manually to get better performance, then the
compiler has a bug.

The only reason not to use uint32_t is because some platforms don't support=
 it,
and as I've already said that's not relevant for this implementation.=