Bitcoin Core

This commit adds a new reusable GitHub Actions step that sets environment variables for Bitcoin Core's continuous integration (CI) system. It defines build/cache directories and computes cache hashes from source files. There is no user-facing or network-facing change, and nothing in the diff suggests a security vulnerability or fix.

This commit adds two new GitHub Actions helper files that manage caching for the project's continuous integration (CI) build system. It saves and reuses compiled code and dependency downloads to make automated builds faster. There is no indication this change introduces a security vulnerability or modifies any Bitcoin Core software code that users run.

This commit simply changes two function declarations in a header file from regular methods to virtual methods. Virtual methods can be overridden in subclasses, which is useful for testing with mock objects. There is no security issue here.

This is a tiny documentation-only change in a test helper file. It removes one outdated sentence from a docstring because a previous commit removed the assumption it described. No code behavior changed, and there is no security relevance.

This commit simply doubles a default internal setting that controls how much data Bitcoin Core groups together before writing to its UTXO database. It is a performance tuning change, not a security fix or vulnerability. There is no indication it introduces a security problem.

This is a simple code cleanup change: a single default value for a database batch size setting is moved from one header file to another and renamed to follow project conventions. The actual numeric value (16 MiB) and how it is used remain unchanged. There is no security relevance.

This change narrows the use of a global lock in the getblocktemplate RPC, which miners use to request work. The lock is now acquired later and held for a shorter time, rather than being held across the entire request setup. This is a performance and correctness cleanup. There is no direct evidence in the commit that it fixes an exploitable security bug, but reducing lock scope can prevent subtle race conditions or RPC stalls.

This is a routine Continuous Integration (CI) maintenance change for Bitcoin Core. It switches the CentOS test container back from using the ksh shell to the dash shell, because a Red Hat bug that previously required ksh has been fixed. The change only affects internal test scripts and installed CI packages; it does not touch Bitcoin Core's network code, wallet, consensus logic, or any user-facing software.

This commit undoes a recent code cleanup that changed how Bitcoin Core's memory pool tracks transactions for compact block reconstruction. The reversion restores the previous design where the mempool keeps pairs of transaction IDs and iterators, rather than storing direct shared references to transactions. There is no indication in the commit itself that this fixes a security bug; it appears to be a design or correctness revert, possibly due to bugs introduced by the original refactor.

This commit adds a new performance test (benchmark) for Bitcoin Core's compact block reconstruction feature. It does not change any production code that runs on the live Bitcoin network, so it cannot directly cause security problems or be exploited by attackers.

This commit undoes a recent code cleanup in Bitcoin Core's compact block reconstruction feature. The original cleanup changed an internal list of spare transactions from storing pairs of 'transaction ID + transaction pointer' to storing only the transaction pointer. This revert restores the paired format and adds a comment explaining that keeping both values together improves CPU cache performance during block reconstruction. There is no direct evidence in the commit that this fixes an active security bug, but it is a defensive revert of a performance refactor in a consensus-adjacent code path.

This commit simply updates the continuous integration (CI) test scripts to use LLVM/Clang version 21 instead of version 20. It does not change Bitcoin Core's actual source code, network behavior, or wallet logic. There is no security issue here.

This commit only changes a continuous integration (CI) test configuration file. It adds an environment variable that limits stack size during automated testing of a 32-bit Intel build. There is no change to the actual Bitcoin Core software that users run, and nothing in the commit suggests a security fix or vulnerability.

This commit fixes a bug in Bitcoin Core's own testing tools. The test framework had a limit meant to avoid passing overly long command-line arguments to the bitcoin-cli program, but it was checking the size of the largest single argument instead of the total size of all arguments. The fix lowers the threshold and checks the total length, and adds tests to make sure large arguments still work by routing them through standard input instead. This is a test-only change and does not affect the Bitcoin Core software that users run.

This commit updates the libmultiprocess subtree used by Bitcoin Core. The most notable change is a build-time guard that refuses to compile against specific old versions of the Cap'n Proto library because those versions contain a known memory-access vulnerability (CVE-2022-46149). The commit also adds CI testing for older Cap'n Proto versions and OpenBSD, fixes a C++20/Cap'n Proto 0.8 compatibility issue in the code generator, removes an obsolete linker flag, and adds a missing include. It is primarily a hardening and compatibility update, not a fix for a new vulnerability in Bitcoin Core itself.

This commit removes a now-impossible error path in Bitcoin Core's wallet code. Legacy (non-descriptor) wallets have already been removed from the codebase, so the check that rejected adding descriptors to a legacy wallet was unreachable 'dead code.' The change replaces that check with an internal assertion, which only affects debug builds and only crashes the program if an invariant that should never happen is violated. There is no security vulnerability here.

This commit removes two unused C++ template instantiations from Bitcoin Core's synchronization code. Template instantiations are pre-compiled versions of a generic function for specific data types. The removed ones supported older mutex types that are no longer used by the ENTER_CRITICAL_SECTION macro. This is a routine cleanup with no security impact.

This is a test-only cleanup change. It replaces old-style manual lock/unlock macros with safer automatic lock helpers in a single test file. There is no change to the actual Bitcoin Core software that users run, and no security bug is being fixed.

This commit only adds two runtime assertions to an existing test file. It does not change any production code, network behavior, wallet logic, or consensus rules. The assertions verify that a helper called reverse_lock correctly releases and re-acquires a mutex during tests. There is no security vulnerability here.

This commit simply deletes two unused C++ macros (ENTER_CRITICAL_SECTION and LEAVE_CRITICAL_SECTION) from a header file. These macros were non-RAII manual locking helpers that had been replaced by safer scoped lock wrappers. There is no runtime behavior change, no bug fix, and no security vulnerability being patched.

This commit is a small internal cleanup in Bitcoin Core's RPC mining code. It replaces manual lock/unlock macros with a safer, automatic 'reverse lock' helper that temporarily releases a lock and re-acquires it when done. The commit message explicitly says 'No functional change,' and the diff shows only a mechanical code-style swap with no behavior change visible.

This commit only updates documentation for building Bitcoin Core on Alpine and Arch Linux. It adds instructions to install the Cap'n Proto library, which is needed for a new optional inter-process communication (IPC) feature, and mentions how to disable that feature if not needed. There are no code changes and no security fix or vulnerability introduced.

This is a one-line documentation update for Fedora Linux build instructions. It adds an extra package name (capnproto-devel) so developers can compile Bitcoin Core's optional inter-process communication (IPC) feature. There is no code change, no bug fix, and no security issue in the commit itself.

This commit adds a new automated test for Bitcoin Core's coin statistics index. It checks that after a blockchain reorganization and an unclean shutdown, the index correctly rewinds to the last safely saved point. The commit itself is only a test file change and does not modify production code.

This change fixes a crash-and-restart bug in Bitcoin Core's index tracking. Previously, during a blockchain reorganization (a 'reorg'), an index could save its new position to disk before the main chain data was fully flushed. If the computer then shut down uncleanly, the index could point to blocks that had already been pruned away, leaving the index corrupted on restart. The fix removes that premature save so the index only commits its position when the main chain state is safely flushed.