Summary:
scan-build is reporting two memory leak bugs in `table/block_based_table_reader.cc`. They are both false positives. In both cases we allocate memory in `ReadBlockFromFile` if `s.ok()`. Then after the function `ReadBlockFromFile` returns we check for the same variable if `s.ok()` and then use the memory that was allocated. The bugs reported by scan-build is if `ReadBlockFromFile` allocates memory and returns, but for some reason status `s` is not the same and `s.ok() != true`.
In this case scan-build is concerned that memory owner transfer is not explicit. I modified `ReadBlockFromFile` to accept `std::unique_ptr<Block>*` as a parameter, instead of raw pointer.
scan-build reports:
http://home.fburl.com/~sugak/latest2/report-a4b3fa.html#EndPathhttp://home.fburl.com/~sugak/latest2/report-29adbf.html#EndPath
Test Plan:
Make sure scan-build does not report these bugs and all tests are passing.
```lang=bash
% make check
% make analyze
```
Reviewers: sdong, lgalanis, meyering, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D33681
98870c7b9c