https://emscripten.org/docs/getting_started/index.html
-DCMAKE_TOOLCHAIN_FILE=/<path>/<to>/emsdk/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake
open build.emscripten/index.html
https://emscripten.org/docs/getting_started/index.html
-DCMAKE_TOOLCHAIN_FILE=/<path>/<to>/emsdk/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake
open build.emscripten/index.html