DUMA (Detect Unintended Memory Access) stops your
program on the exact instruction that overruns (or
underruns) a malloc() memory buffer. GDB will then
display the source-code line that causes the bug.
It works by using the virtual-memory hardware to
create a red-zone at the border of each buffer:
touch that, and your program stops. It can catch
formerly impossible-to-catch overrun bugs. DUMA is
a fork of Bruce Perens' Electric Fence library.
