build and install gcc to $prefix, then run:
LD_LIBRARY_PATH=$prefix/lib64 CXX=$prefix/bin/g++ make run

this test has a custom handle_contract_violation that throws an exception
this test is built with -fcontract-continuation-mode=on

since 1) our fun() *IS* marked noexcept even though 2) the continue mode is
set to on, we expect the exception thrown within the contract violation
handler to quashed and have std::terminate run.

expected output therefore ends in:
	terminate called after throwing an instance of 'int'

despite there being a catch(int &) handler in main