[38.4] How can I decompile an executable program back into C++ source code?
You gotta be kidding, right?
Here are a few of the many reasons this is not even remotely feasible:
- What makes you think the program was written in C++ to begin
- Even if you are sure it was originally written (at least partially)
in C++, which one of the gazillion C++ compilers produced it?
- Even if you know the compiler, which particular version of the
compiler was used?
- Even if you know the compiler's manufacturer and version number,
what compile-time options were used?
- Even if you know the compiler's manufacturer and version number and
compile-time options, what third party libraries were linked-in, and what was
- Even if you know all that stuff, most executables have had their
debugging information stripped out, so the resulting decompiled code will be
- Even if you know everything about the compiler, manufacturer,
version number, compile-time options, third party libraries, and debugging
information, the cost of writing a decompiler that works with even one
particular compiler and has even a modest success rate at generating code
would be significant — on the par with writing the compiler itself from
But the biggest question is not how you can decompile someone's code,
but why do you want to do this? If you're trying to reverse-engineer
someone else's code, shame on you; go find honest work. If you're trying to
recover from losing your own source, the best suggestion I have is to make
better backups next time.
(Don't bother writing me email saying there are legitimate reasons for
decompiling; I didn't say there weren't.)