swieros

https://github.com/rswier/swieros is a cool project that uses it's own VM (with a C compiler included). I was surprised by all the capabilities it has.

The C4 compiler is certainly fascinating and worth studying but don't believe that swieros's C compiler is based on that judging by their code [1][2]. There are similarities of course but well they are compiling the same language after all using some similar standard techniques like recursive descent parser [3]. Anyways, C4 is also very cool and focused on minimalism. Swieros's compiler seems much more extensive and even includes #define as the other comment mentioned and va_args. [1] https://github.com/rswier/swieros/blob/master/root/bin/c.c [2] https://github.com/rswier/c4/blob/master/c4.c [3] https://en.wikipedia.org/wiki/Recursive_descent_parser

There's a very interesting C interpreter/compiler there [1]. From the header: "c is the c compiler. It takes a single source file and creates an executable file or else executes the compiled code immediately. The compiler does not reach full standards compliance, so some programs need minor adjustment. There is no preprocessor, although the #include keyword is allowed supporting a single level of file inclusion." [1] https://github.com/rswier/swieros/blob/master/root/bin/c.c

c4 is very cool, but it's not a compiler in the usual sense of the term. It compiles to a kind of bytecode which it then interprets (like Python, for example), but it doesn't generate assembly or machine code (like GCC or JIT compilers, for example). But there's a more realistic compiler inside swieros: https://github.com/rswier/swieros/blob/master/root/bin/c.c that emits actual "binaries" for the emulated toy CPU. It's hard to tell what exactly is going on though, as this is not "very readable and simple code".

I love c4. The author writes very readable and simple code. I recommend trying out swieros as well “a tiny Unix like kernel”: https://github.com/rswier/swieros

c4.c author here - selfie seems to fill a niche between c4 and my other more full featured compiler/os swieros. Very cool! https://github.com/rswier/swieros/blob/master/00README.txt

This isn't the same, but if you're interested in looking at a compiler and OS mostly from scratch based on C check this out. It's pretty amazing. https://github.com/rswier/swieros It comes from the author of the c4 compiler. (Interpreter?)

The guy who did the C4 compiler also has a more fully featured one that does support structures: https://github.com/rswier/swieros/blob/master/root/bin/c.c It's part of an OS he's building based on xv6

The overview/explanation that ought to be visible is in a file[0]. It is still not clear the extent of this or its derivation, how much is borrowed and how much original, and generally why it exists. [0] https://github.com/rswier/swieros/blob/master/00README.txt

I assume it's a minified version of the other C compiler in his Github account, which does have better variable names and some comments. https://github.com/rswier/swieros/blob/master/root/bin/c.c