Getting Catch2 v3 to work in alpine docker image

I have tried it today and so far Catch2 v2 works either using package installer or through dropping its header file or compiling its library from its github source code.

But for Catch2 v3, it also works but to compile our binary, we have to either use library Catch2Main to autogenerate main or create our own main code because alpine with Catch2 v3 does not work with auto-generation of main using #define CATCH_CONFIG_MAIN flag

test_main.cpp (alpine with catch2 does not work with this kind of auto-generated main flag)

#define CATCH_CONFIG_MAIN
#include <catch2/catch_all.hpp>

main.cpp (works since we defined our own main)

#include <catch2/catch_session.hpp>

int main(int argc, char* argv[]) {
    Catch::Session session;
    return session.run(argc, argv);
}

Or also work with Library mode with Catch2main to auto generate main

✅ this works since we use Catch2Main library

g++ test_math.cpp -o test -I/usr/local/include -L/usr/local/lib -lCatch2Main -lCatch2 

❌ this does not work as I have verified that #define CATCH_CONFIG_MAIN flag is not working

g++ test_main.cpp test_math.cpp -o test -I/usr/local/include

✅this works since we wrote our own main

g++ main.cpp test_math.cpp -o test -I/usr/local/include -lCatch2