I'm constantly amazed at the width and breadth of development material on the Web, from Source Code, Operating Systems and free Compilers.
The latest discovery is CH. As their website says. Ch is the most complete C interpreter and C virtual machine in existence. Ch is embeddable in other application programs and hardware. There are several versions of which only the Standard version is free but it is definitely not a poor cousin with over 8.000 C functions.
Ch Standard Edition offers a very high-level language (VHLL) environment for general-purpose computing. Virtually any C programs can readily run in the Ch language environment across different platforms without lengthy compile/link/execute/debug cycles. Ch can also easily call functions in binary C/C++ libraries.
I'll be giving CH a review and assess its suitability for the C Tutorial. Meanwhile here are some other links for other free Compilers.