Add experimental CFG recovery frontend based on Dyninst

[Aiethel]

Dear McSema maintainers,

I tried to fix #295 and I think I created somewhat decent implementation that passes all basic tests included in original repository.

However there are two things I am not exactly happy about.
No matter what I was not able to get rid of -std=gnu++11 flag, that always gets appended to the end of make flags, but program needs newer standard. (Right now it needs manual overwrite)
Second one is that I had to modified one condition in /BC/Function.cpp I believe it is harmless but you may have another opinion, so let me know and I will try to fix it somehow else.

There are probably more than a few things that are not working, but as it is, it should be a solid basic block.

Regards
Lukáš Korenčik

[artemdinaburg]

Did CMAKE_CXX_STANDARD work?

We may also force a standard on the runtimes code. Can @alessandrogario or @pgoodman comment more?

[alessandrogario]

The CMAKE_CXX_STANDARD and CMAKE_CXX_EXTENSIONS variables (leading to g++11) are being set from the remill CMake file: https://github.com/trailofbits/remill/blob/master/CMakeLists.txt#L121 and https://github.com/trailofbits/remill/blob/master/CMakeLists.txt#L125

We should probably avoid setting it like that for everything in the project! In the meanwhile, you can overwrite it directly on your target:

set_target_properties(mcsema-dyninst-disass PROPERTIES CXX_STANDARD 14 CXX_STANDARD_REQUIRED YES CXX_EXTENSIONS NO)

[Aiethel]

Thanks I have changed it accordingly. I also made some workaround so there is no need to change things in base project (except for CMakeList of course).

[pgoodman]

@kumarak Can you run some of your own IDA-based exception tests, using this as the linux.txt, and let me know if there are issues?

[kumarak]

I will update the branch with master and run the exception testcases.

[kumarak]

The exception tests look good.

[artemdinaburg]

Closing the PR for now since there is an updated version of DynInst-based CFG recovery in development.