First, I upgrade the solution to build under VC++ 2015.
Then I press f5.
The code compiles cleanly.
Running the code produces the following output…

Debug Assertion Failed!

Program: C:\WINDOWS\SYSTEM32\MSVCP140D.dll
File: c:\program files (x86)\microsoft visual studio 14.0\vc\include\xstring
Line: 75

Expression: string iterator not dereferencable

For information on how your program can cause an assertion
failure, see the Visual C++ documentation on asserts.

(Press Retry to debug the application)

utils.cpp 255
if (*argp == '\'' || *argp == '"')

I am running the latest Windows 10 Insider build.

Any ideas?

Try this…

if (argp != argument.end() && *argp == '\'' || *argp == '"')