Design: Why are array inputs to Block-Algorithms not const

[pauleonix]

I.e. why

__device__ __forceinline__ T 	cub::BlockReduce::Sum (T(&inputs)[ITEMS_PER_THREAD])

Instead of

__device__ __forceinline__ T 	cub::BlockReduce::Sum (const T(&inputs)[ITEMS_PER_THREAD])

?
The way it is written right now makes const-correct code impossible.

[gevtushenko]

Hello @pauleonix!

I agree, it should be const. I can speculate that the initial reason was to allow binary operator to accept non-const lvalues. We probably need something along the lines of std::reduce in our docs as well:

The behavior is undefined if binary_op modifies any element

[pauleonix]

Should I open an issue for this?

[gevtushenko]

@pauleonix sure! This is an issue.