An award-winning instrumentation framework for building dynamic analysis tools
BS Editor: Valgrind is an award-winning instrumentation framework for building dynamic analysis tools. There are Valgrind tools that can automatically Detect many memory management and threading bugs, and profile your programs in detail. You can also use Valgrind to build new tools.

The Valgrind distribution currently includes five production-quality tools: a memory error detector, a thread error detector, a cache and branch-Prediction proFILEr, a call-graph generating cache profiler, and a heap profiler. It also includes two experimental tools: a data race detector, and an Instant Memory leak detector. It runs on the following platforms: X86/Linux, AMD64/Linux, PPC32/Linux, PPC64/Linux.

Valgrind is Open Source / Free Software, and is freely available under the GNU General Public License.
3.4.1 is a bug-fix release that fixes some regressions and assertion
failures in debug info reading in 3.4.0, most notably incorrect stack
traces on amd64-linux on older (glibc-2.3 based) systems. Various
other debug info problems are also fixed. A number of bugs in the
exp-ptrcheck tool introduced in 3.4.0 have been fixed. you can free download Valgrind 3.4.1 now.