I am running g++ 4.8.5 on RHEL, so some of the date class methods would not compile for me. I like run g++ with the -Wall and -Werror flags as well, which trigger verbose warnings and turn all warnings into errors. This is a personal preference, but also helps me write better code.
I downloaded the code from here http://www.zebra0.com/cpp/classes/date1.php and refactored the Date class to comply with my compiler, which required a few significant changes...
1. _strdate_s does not work with GCC.
2. Declaring days2 as a static int array in Date.h triggers -Werror. This should be a const int array.
3. The invalid argument exception requires including <stdexcept> in GCC.
4. Removing some duplicate code.
I've attached my refactors of the class.
date.cpp
date.h
main.cpp
Makefile.txt
I am running g++ 4.8.5 on RHEL