prog.cpp: In function ‘int main()’:
prog.cpp:8:10: error: no matching function for call to ‘foo::foo(int)’
prog.cpp:8:10: note: candidates are:
prog.cpp:1:8: note: foo::foo()
prog.cpp:1:8: note: candidate expects 0 arguments, 1 provided
prog.cpp:1:8: note: foo::foo(const foo&)
prog.cpp:1:8: note: no known conversion for argument 1 from ‘int’ to ‘const foo&’