Working build configuration for truebit proof-of-concept "coindrop" example

README_truebit_simple.md

EMSCRIPTEN SETUP

https://github.com/juj/emsdk @ 2324e5d8

• LLVM_CMAKE_ARGS="-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=WebAssembly" emsdk install sdk-tag-1.37.28-64bit (be patient!)

To activate correct paths for emscripten and dependencies use:

• ./emsdk activate sdk-tag-1.37.28-64bit
• ./emsdk_env.sh

TRUEBIT SETUP

https://github.com/TrueBitFoundation/ocaml-offchain @ 9e3fc4ff

• cd interpreter && make -> will build executable wasm

https://github.com/TrueBitFoundation/emscripten-module-wrapper @ 46948d8d

• In /prepare.js paths are hardcoded. Edit the lines at the top starting with var dir = and var wasm = to reflect own setup. The latter is the wasm executable above (NOT the submodule)

https://github.com/TrueBitFoundation/coindrop @ 6b92edaa

• touch input.bin
• touch output.bin
• EMCC_WASM_BACKEND=1 emcc -s WASM=1 simple.c -o simple.js (this step first downloaded and compiled additional code) -> will produce:

simple.js
simple.wast.mappedGlobals
simple.wasm
simple.wast

• /path/to/emscripten-module-wrapper/prepare.js simple.js --file input.bin --file output.bin -> produces a dir with content as such:

-rw-r--r-- 1 lash lash    185 Jan 18 18:46 globals.json
-rw-r--r-- 1 lash lash  42436 Jan 18 18:46 globals.wasm
-rw-r--r-- 1 lash lash      0 Jan 18 18:46 input.data
-rw-r--r-- 1 lash lash  42335 Jan 18 18:46 merge.wasm
-rw-r--r-- 1 lash lash      0 Jan 18 18:46 output.data
-rw-r--r-- 1 lash lash 238222 Jan 18 18:46 prepared.js
-rw-r--r-- 1 lash lash      0 Jan 18 18:46 record.bin
-rw-r--r-- 1 lash lash  32795 Jan 18 18:46 simple.wasm
-rw-r--r-- 1 lash lash  33180 Jan 18 18:46 underscore.wasm

could you please update this gist file. As I see that this link is not working: https://github.com/TrueBitFoundation/coindrop