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Fix UB in benchmark #96

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Fix UB in benchmark #96

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@hebasto hebasto commented Jun 2, 2025 •
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From https://en.cppreference.com/w/c/language/operator_arithmetic.html:

The behavior is undefined if rhs is negative or is greater or equal the number of bits in the promoted lhs.

Steps to reproduce on Ubuntu 25.04 using the master branch @ ea8f66b:

$ ./autogen.sh
$ ./configure --enable-benchmark CXX=clang++-20 CXXFLAGS="-O0"
$ make bench -j $(nproc) bench
$ ./bench
<snip>
recover[ms]	 63	 260.72278	         -	  62.21269	
create[ns]	 63	  79.66483	         -	  17.74962	
/usr/lib/gcc/x86_64-linux-gnu/15/../../../../include/c++/15/bits/uniform_int_dist.h:108: std::uniform_int_distribution<unsigned long>::param_type::param_type(_IntType, _IntType) [_IntType = unsigned long]: Assertion '_M_a <= _M_b' failed.
Aborted (core dumped)

@hebasto
Fix UB in benchmark
abc7bef 
From https://en.cppreference.com/w/c/language/operator_arithmetic.html:
> The behavior is undefined if rhs is negative or is greater or equal
> the number of bits in the promoted lhs.
@hebasto hebasto mentioned this pull request Jun 2, 2025
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