Clang for P2

• Clang is a well known C++ compiler front end for the LLVM compiler back end.

  • Many thanks to forum member n_ermosh for all the hard work on this and also iseries for testing

• Update 16Apr2026:  P2 forum member @Rogloh has made improvements so that Clang can compile Micropython

  • Here's a zip of Clang folder for Windows that can compile hello.c  

  • Now includes fixes from Rogloh (so modulus operator won't break it).  hello2.c tests this...

  • Compile using instructions in this thread (post #42), or see "build.bat" for example on how to build

    • Can run "build hello" to compile and build hello.c

    • Can use loadp2.exe to upload to P2 (see instructions in build.bat).  Or, use tool like FlexProp to upload binary to P2.

• NOTE:  Things below are OLD (do not use)

• Download a 600MB Clang folder for Windows, ready to go. 

  • Just unzip somewhere and then update "start in" folder in command prompt and first line of build.bat with new path of the bin folder

    • Then, type "build serial" and then "load serial" to get Hello World Example run

    • Or, type "build test" and "load test"

• To Build yourself:  Recent posts in the C/C++ Parallax forum suggests it may be ready for use

  • Build instructions are given in post #133 in this thread

    • Note:  Skip the "cd build" step.

    • Github source is here:  GitHub - ne75/p2llvm: Contains Propeller 2 Library, C Standard Library, examples, and documentation for p2llvm

  •  Prerequisites to build:

    • install git from here: https://git-scm.com/download/win (Use all default settings when installing)

    • get cmake latest releast from here and let it add cmake to the path: https://cmake.org/download/

    • download and install Python3 from here: https://www.python.org/downloads/ (let it add python to path)

  • Note:  To actually compile, you also need libc.a and libp2.a and loadp2.exe

    • These can't currently be compiled with cmake, so need to get them some other way

    • Some versions of libc.a include debug code and produce large elf files.

      • Seems the elf file can be bigger than 512kB, but less actually gets loaded

  • To compile things with printf, you need to copy libc with stdio.h in it over to the build folder.