Nulgrind: The Minimal Valgrind Tool; Overview - Valgrind Software Quick Start Manual

14. Nulgrind: the minimal Valgrind tool

To use this tool, you must specify --tool=none on the Valgrind command line.

14.1. Overview

Nulgrind is the simplest possible Valgrind tool. It performs no instrumentation or analysis of a program, just runs it
normally. It is mainly of use for Valgrind's developers for debugging and regression testing.
Nonetheless you can run programs with Nulgrind. They will run roughly 5 times more slowly than normal, for no
useful effect. Note that you need to use the option --tool=none to run Nulgrind (ie. not --tool=nulgrind).
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