In commit fc3b4caa (Memory management: cast functions for managed pointers,
2019-11-18) we added a check to `Source/Checks/cm_cxx17_check.cpp` to avoid
using C++17 mode on a compiler that does not support all our C++17 usage.
Add the check to our bootstrap script too.
In commit fc3b4caa (Memory management: cast functions for managed pointers,
2019-11-18) we added a check to `Source/Checks/cm_cxx17_check.cpp` to avoid
using C++17 mode on a compiler that does not support all our C++17 usage.
Add the check to our bootstrap script too.
