[jira] [Created] (ARROW-14065) FixedSizeBinaryBuilder behaves incorrectly since v5.0 with "Resize+Advance" operation

["Tao He (Jira)" <ji...@apache.org>]

Tao He created ARROW-14065:
------------------------------

             Summary: FixedSizeBinaryBuilder behaves incorrectly since v5.0 with "Resize+Advance" operation
                 Key: ARROW-14065
                 URL: https://issues.apache.org/jira/browse/ARROW-14065
             Project: Apache Arrow
          Issue Type: Bug
          Components: C++
    Affects Versions: 5.0.0
            Reporter: Tao He


With the following code, we first "Resize" a builder, then fill the content, and finally use "Advance" to move the pointer to the end,

 ```cpp
#include <iostream>
#include <memory>

#include "arrow/array/array_binary.h"
#include "arrow/array/builder_binary.h"
#include "arrow/status.h"
#include "arrow/util/config.h"

int main(int argc, char** argv) {
    struct S {
      int64_t a;
      double b;
    };
    arrow::FixedSizeBinaryBuilder b1(arrow::fixed_size_binary(sizeof(S)));

    arrow::FixedSizeBinaryBuilder b4(arrow::fixed_size_binary(sizeof(S)));
    b4.Resize(10);

    // ... fill the array data in random-access fashion ...

    b4.Advance(10);

    std::shared_ptr<arrow::FixedSizeBinaryArray> a4;
    b4.Finish(&a4);

    std::cout << "array length: " << a4->length() << std::endl;
    std::cout << "buffer size: " << a4->values()->size() << std::endl;

    return 0;
}
```

The output is 10 and 160 with arrow 4.0 (which is desired behavior) however arrow 5.0 yields 10 and 0, which means the length of array is not 0 but the underlying buffer is a null pointer.

The same error doesn't happen to other types, e.g., IntBuilders.





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