Valgrinds

Valgrind is a dynamic instrumentation framework used for building debugging and profiling tools for memory and threading errors in native programs. It executes programs on its own synthetic machine, instrumenting memory accesses, allocations, and function calls at runtime. Valgrind is free software released under the GNU General Public License and is maintained by a community of contributors.

The suite comprises several tools commonly referred to as Valgrind tools. Notable components include Memcheck, which detects memory management and usage errors (such as use-after-free, invalid reads and writes, and leaks); Helgrind, which detects data races in multi-threaded programs; Cachegrind, which models CPU caches to estimate cache misses; Massif, a heap profiler; and Callgrind, which records call graphs for performance analysis.

Usage generally involves invoking the Valgrind runner with a selected tool, for example: valgrind --tool=memcheck --leak-check=full --show-leak-kinds=all ./program [args]. Other tools are selected with --tool=cachegrind, --tool=massif, or --tool=helgrind. Options can control reporting detail and performance, such as --track-origins for uninitialized memory and --log-file.

Limitations include substantial slowdown and increased memory usage, making it unsuitable for production runs. Support spans Linux and several Unix-like systems, but portability to Windows and some macOS variants varies, and some languages or environments (notably those with aggressive JIT or non-native code) may be less compatible.

Valgrind was created by Julian Seward in 2000 and is released under the GPL. It is widely used for debugging and profiling in C, C++, and Fortran projects.