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0 pointsjhasse9mo ago0 comments

uniform_int_distribution differs between compilers/platforms! Don't use it if you don't want true randomness.

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Thank you, that makes sense. I can see that being an issue for testing.

I wouldn't describe "pseudo-random sequences that differ between compilers/platforms/versions but are deterministic for a given toolchain" as "true randomness" but I understand the point.

I have confirmed that uniform_int_distribution gives different results on x86-64 clang (trunk) with libc++ [1] vs x86-64 clang (trunk) with libstdc++ [2].

[1]: https://godbolt.org/z/dd5YMs7zo

[2]: https://godbolt.org/z/8svGn7Exc

j / k navigate · click thread line to collapse

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senkora9mo ago

Thank you, that makes sense. I can see that being an issue for testing.

I wouldn't describe "pseudo-random sequences that differ between compilers/platforms/versions but are deterministic for a given toolchain" as "true randomness" but I understand the point.

I have confirmed that uniform_int_distribution gives different results on x86-64 clang (trunk) with libc++ [1] vs x86-64 clang (trunk) with libstdc++ [2].

[1]: https://godbolt.org/z/dd5YMs7zo

[2]: https://godbolt.org/z/8svGn7Exc

j / k navigate · click thread line to collapse