Summary:
Make `autovector` constructs the stack based element in place before move or copy another `autovector`'s stack based elements. This is already done in the move/copy version of `autovector::push_back` when adding item to the stack based memory
8e6e8957fb/util/autovector.h (L269-L285)
The ` values_ = reinterpret_cast<pointer>(buf_);` statement is not sufficient to ensure the class's member variables are properly constructed. I'm able to reproduce this consistently in a unit test in this change: https://github.com/facebook/rocksdb/compare/main...jowlyzhang:fix_sv_install with unit test:
`./tiered_compaction_test --gtest_filter="\*FastTrack\*"
With below stack trace P1203997597 showing the `std::string` copy destination is invalid, which indicates the object in the destination `autovector` is not constructed properly.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12499
Test Plan: Existing unit tests.
Reviewed By: anand1976
Differential Revision: D55662354
Pulled By: jowlyzhang
fbshipit-source-id: 581ceb11155d3dd711998607ec6950c0e327556a
