-e: see above, il2cpp.exe fails with errors (see log) stopping the build
--works with 5.6.2f1, stops working with 2017.1b2
--Windows 7 with all latest Windows (July 11th)
--also installed https://www.microsoft.com/en-gb/download/details.aspx?id=48145 which didn't solve the issue

-repro:
--install a clean Win7 version (used a VM)
--install 2017.1 build
--start a WebGL build
--NOTICE that it fails with errors starting with:

stdout:
Building build.bc with EmscriptenToolChain.
Output directory: C:\Users\Stefan\Documents\New Unity Project\Temp\StagingArea\Data\Native
Cache directory: C:\Users\Stefan\Documents\New Unity Project\Library\il2cpp_cache
il2cpp.exe didn't catch exception: Unity.IL2CPP.Building.BuilderFailedException: INFO:root:Checking JS engine ['C:/Program Files/Unity/2017.1.0f2/Editor/Data\\Tools\\nodejs\\node.exe', '--stack_size=8192', '--max-old-space-size=2048'] failed. Check your config file. Details: Expected the command ['C:/Program Files/Unity/2017.1.0f2/Editor/Data\\Tools\\nodejs\\node.exe', '--stack_size=8192', '--max-old-space-size=2048', 'C:\\Program Files\\Unity\\2017.1.0f2\\Editor\\Data\\PlaybackEngines\\WebGLSupport\\BuildTools\\Emscripten\\src\\hello_world.js'] to finish with return code 0, but it returned with code -1073741819 instead! Output:
WARNING:root:did not see a source tree above or next to the LLVM root directory (guessing based on directory of C:\Program Files\Unity\2017.1.0f2\Editor\Data\PlaybackEngines\WebGLSupport\BuildTools\Emscripten_FastComp_Win\llc), could not verify version numbers match
INFO:root:(Emscripten: Running sanity checks)
CRITICAL:root:The JavaScript shell used for compiling (['C:/Program Files/Unity/2017.1.0f2/Editor/Data\\Tools\\nodejs\\node.exe', '--stack_size=8192', '--max-old-space-size=2048']) does not seem to work, check the paths in C:\Program Files\Unity\2017.1.0f2\Editor\Data\PlaybackEngines\WebGLSupport\BuildTools\emscripten.config