A C to WebAssembly compiler written in OCaml
In order to build the compiler you will need an OCaml compiler, dune, and the menhir and cmdliner libraries installed, you can then build the compiler with the command:
dune build
In order to compile a C program, you can use the command:
minic prog.c
By default, the output program is sent on standard output, you can use the -o option to send it to a file, the full list of options can be seen with the command
minic --help
The output format is WebAssembly's textual format, the generated file can then be compiled to the binary format using the wat2wasm tool from the WebAssembly binary toolkit.
A wasm program which was compiled by minic can be executed on the command line using deno and the typescript runtime located in the runtime directory. For example, from the root directory:
dune exec ./bin/minic.exe -- prog.c -o prog.wat
wat2wasm prog.wat
deno run --allow-read --quiet runtime/runtime.mts prog.wasm
will compile prog.mnc, create the corresponding binary wasm file, and execute its code using the runtime.
These programs can also be executed in an internet browser using https://github.com/tretre91/mnc_runtime.
Note: A program which doesn't include stdio.h can be used as a standalone WebAssembly module, as it won't depend on any imported function
Tests are located in the test directory, executing the tests will require that you have deno, wabt (for wat2wasm), the patdiff library and gcc installed.
You can then run the tests with:
dune runtest
Features which are not currently implemented include:
- The address operator (&)
- Multidimensional arrays (
int matrix[5][6];) - increment and decrement operators (
++and--) - assignments operators (
a += 2,b *= 3, etc) - assignments as expressions (
int a; if (a = 5) {...) - single line blocks (
if (true) ...;,while(false) ...;) - structures
- typedefs
A small subset of the C standard library is included (putchar, puts, malloc, free and some functions from string.h), the source files related to the standard library can be found in the include directory.
A basic preprocessor is also included, the available directives are #define (for simple macros only), #undef, #include, #ifdef, #ifndef and #endif.