Get a clan error when compiling a SIMPLE C program using GCC under my mac book pro : i just write a simple c program as follows:

    int main(int argc, char *argv[])
    { 	return argc; }

However, when I compile and link the program, I encounter a Clang error. What's up with the setting or gcc?

    LB:test liangbin$ gcc ./src/test_main.c -o ./obj/test_main.o
    LB:test liangbin$ gcc ./obj/test_main.o -o ./bin/test_main
    ld: can't link with a main executable file './obj/test_main.o' for architecture x86_64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)*


[enter image description here][1]

  [1]: https://i.stack.imgur.com/pNY95.jpg