[GitHub] [arrow] mapleFU commented on pull request #15241: GH-14923: [C++][Parquet] Fix DELTA_BINARY_PACKED problem on reading the last block with malford bit-width

[GitBox]

mapleFU commented on PR #15241:
URL: https://github.com/apache/arrow/pull/15241#issuecomment-1374523168

   Well, it's a bit weird.
   
   ```c++
   TEST_F(DeltaBitPackEncoding, MalfordMiniblockBitWidth) {
     std::shared_ptr<ColumnDescriptor> descr_ = ExampleDescr<Int32Type>();
     auto decoder = MakeTypedDecoder<Int32Type>(Encoding::DELTA_BINARY_PACKED, 
descr_.get());
     using c_type = parquet::Int32Type::c_type;
   
     unsigned char good_data[] = "\200\001\004A\237\224\316\362\r\242\220\203-  
";
     int encode_buffer_size = 273;
     int num_values = 65;
     std::vector<uint8_t> output_bytes = std::vector<uint8_t>(num_values * 
sizeof(c_type));
     auto decode_buf = reinterpret_cast<c_type*>(output_bytes.data());
     decoder->SetData(num_values, &good_data[0], encode_buffer_size);
   ```
   
   @rok How do you build the `good_data`? Seems `encode_buffer_size = 273` is 
too large for `good_data`, and in `Release` mode, memcpy will reach the stack 
guard, and raise an asan exception.


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscr...@arrow.apache.org

For queries about this service, please contact Infrastructure at:
us...@infra.apache.org