refactor, bench, fuzz: Drop unneeded UCharCast calls #29820

1. 
   hebasto commented at 2:50 pm on April 6, 2024: member

   The CKey::Set() template function handles std::byte just fine: https://github.com/bitcoin/bitcoin/blob/b5d21182e5a66110ce2796c2c99da39c8ebf0d72/src/key.h#L105

   Noticed in #29774 (review).

2. refactor, bench, fuzz: Drop unneeded `UCharCast` calls

   The `CKey::Set()` template function handles `std::byte` just fine.

   56e1e5dd10
3. 
   DrahtBot commented at 2:50 pm on April 6, 2024: contributor

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4. 
   maflcko commented at 9:04 am on April 7, 2024: member

   lgtm ACK 56e1e5dd10cbe51d3abc3fbf532b6b41bf62a889

   A (more invasive) alternative would be to use Set(Span<std::byte>), or Set(Span<BasicByte>)

5. 
   laanwj commented at 3:58 pm on April 9, 2024: member

   Seems fine, code review ACK 56e1e5dd10cbe51d3abc3fbf532b6b41bf62a889
6. 
   hernanmarino commented at 7:56 pm on April 9, 2024: contributor

   ACK 56e1e5dd10cbe51d3abc3fbf532b6b41bf62a889
7. fanquake merged this on Apr 9, 2024
8. fanquake closed this on Apr 9, 2024

   ---

9. hebasto deleted the branch on Apr 10, 2024
10. 
    maflcko commented at 10:34 am on April 10, 2024: member

    Just for reference, the reason this is safe, is not because of the line linked to in the pull request description, but due to the existing UCharCast in the function. Error when trying to pass the wrong type:

    0./key.h:103:26: error: no matching function for call to 'UCharCast'
    1  103 |         } else if (Check(UCharCast(&pbegin[0]))) {
    2      |                          ^~~~~~~~~
    3note: in instantiation of function template specialization 'CKey::Set<__gnu_cxx::__normal_iterator<int *, std::vector<int>>>' requested here
    

Contributors
hebasto DrahtBot maflcko laanwj hernanmarino