catch3/src/catch2/internal/catch_reusable_string_stream.cpp, branch v3.15.3 Progmasoft Catch3: an independently maintained C++17 test framework with a parallel runner, property checks, snapshots and structured results. Fix ReusableStringStream to access the container under the lock (#3031) 2025-09-25T11:31:49+00:00 Duncan Horn 2025-09-25T11:31:49+00:00 f7e7fa0983e83b922cb6336ff3a55d33b2873943 Commit 582200a made `ReusableStringStream`'s index reservation thread safe, however it's still accessing the `m_streams` vector outside the lock. This makes it so that the `add` call returns the pointer in addition to the index so that the lock doesn't need to get acquired again until destruction. The issue with accessing `m_streams` outside the lock is that `add` can call `push_back` on the vector, which might re-allocate. If this re-allocation occurs concurrently with anther thread trying to index into this array, you get UB (typically a null pointer read). 
Commit 582200a made `ReusableStringStream`'s index reservation thread safe, however it's still accessing the `m_streams` vector outside the lock. This makes it so that the `add` call returns the pointer in addition to the index so that the lock doesn't need to get acquired again until destruction.

The issue with accessing `m_streams` outside the lock is that `add` can call `push_back` on the vector, which might re-allocate. If this re-allocation occurs concurrently with anther thread trying to index into this array, you get UB (typically a null pointer read).
 Make message macros (FAIL, WARN, INFO, etc) thread safe 2025-08-23T09:08:18+00:00 Martin Hořeňovský 2025-08-22T22:15:53+00:00 582200a1f8ddd6f435d1264668c7074121c2636c This builds on the existing work to make assertion thread safe, by adding an extra synchronization point in the holder of `ReusableStringStream`'s stream instances, as those are used to build the messages, and finishing the move of message scope holders to be thread-local. 
This builds on the existing work to make assertion thread safe,
by adding an extra synchronization point in the holder of
`ReusableStringStream`'s stream instances, as those are used to
build the messages, and finishing the move of message scope holders
to be thread-local.
Fix references to license file 2022-10-28T09:30:15+00:00 Lars Toenning 2022-10-28T09:22:53+00:00 f1084fb30990fe40c8f5b70034970c7eb4e1da72 The license file was renamed with 6a502cc2f5fedd59b3495b58708f0d6d987ed9e1 
The license file was renamed with 6a502cc2f5fedd59b3495b58708f0d6d987ed9e1
Rename catch_stream -> catch_reusable_string_stream 2022-04-16T14:34:08+00:00 Martin Hořeňovský 2022-04-16T13:00:41+00:00 7b93a2014cb417d277339e3d679cac64bfac237b After everything else was split out, this name much reflects the actual contents of the file(s). 
After everything else was split out, this name much reflects the
actual contents of the file(s).