How to compile C source code without a main function?

Question

How can I compile my C source files without needing to put a main function within them?

I get an error for the .cfiles that have no main fu

Answer 1

You can compile individual files without main, but you cannot link them and of course cannot run them since they are not complete programs. Note that valgrind is not a static analysis tool but a runtime tool, and therefore it is useless on individual translation units not linked into a runnable program.

If you want to test individual files, a common practice is to include something like the following in each file:

#ifdef UNIT_TEST
int main(int argc, char **argv)
{
    /* unit test code goes here */
}
#endif

And compile the file with -DUNIT_TEST.