This test is run as part of the "make leaktest" step during debug build jobs. It uses the [[Performance:Leak_Tools#Trace-malloc|trace-malloc]] tool from [http://mxr.mozilla.org/mozilla-central/source/tools/trace-malloc/ tools/trace-malloc] to wrap calls to malloc and log information about every memory allocation. See also [http://mxr.mozilla.org/mozilla-central/source/build/leaktest.py.in leaktest.py].