WebGL demangle support

In the process of porting a unity web-player app to WebGL I'm running into some issues:

There are runtime errors and the mangled stacktraces make it very hard to understand what is going on.
In the player settings I have enabled Soft Null exceptions and have set Scripting Define Symbols to "DEMANGLE_SUPPORT=1;ASSERTIONS=2".
Yet I get warnings like these in my browser:
a problem occurred in builtin C++ name demangling; build with -s DEMANGLE_SUPPORT=1 to link in libcxxabi demangling
Build with ASSERTIONS=2 for more info.
I'm building via BuildPipeline.BuildPlayer with BuildOptions.AllowDebugging | BuildOptions.Development

These are the sort of stacktraces I get: http://i.imgur.com/ip2yHAR.png

What is the process of enabling demangling and getting proper stacktraces?
Is it possible to hook into the webGL build process at a certain stage?
It is very hard to construct a minimal failure case if it is hard to figure out where the error lies.

 

Is the following kind of a parameter value correct?

Code (CSharp):

1. PlayerSettings.SetPropertyString("emscriptenArgs", "-s DEMANGLE_SUPPORT=1 ASSERTIONS=2 -Werror", BuildTargetGroup.WebGL);

When I set the emscriptenArgs with the above I get the following areas:

Failed running "C:\Program Files (x86)\Unity 5.0.0b19\Editor\Data\PlaybackEngines\webglsupport/BuildTools/Emscripten_Win/python/2.7.5.3_64bit/python.exe" "C:\Program Files (x86)\Unity 5.0.0b19\Editor\Data\PlaybackEngines\webglsupport/BuildTools/Emscripten/emcc" @"C:/Users/sarahm/workspaces/sarahm_default/MiniConstruction/Unity5TestBranch/Unity/Assets/../Temp/emcc_arguments.resp"

stdout:
WARNING: sanity check failed to run [Errno 13] Permission denied: 'C:\\Program Files (x86)\\Unity 5.0.0b19\\Editor\\Data\\PlaybackEngines\\webglsupport/BuildTools/emscripten.config_sanity'
stderr:
WARNING root: did not see a source tree above the LLVM root directory (guessing based on directory of C:\Program Files (x86)\Unity 5.0.0b19\Editor\Data\PlaybackEngines\webglsupport/BuildTools/Emscripten_FastComp_Win\llc), could not verify version numbers match
INFO root: (Emscripten: Running sanity checks)
WARNING root: java does not seem to exist, required for closure compiler, which is optional (define JAVA in ~/.emscripten if you want it)
ERROR root: ASSERTIONS=2: No such file or directory ("ASSERTIONS=2" was expected to be an input file, based on the commandline arguments provided)

UnityEditor.HostView:OnGUI()

How do I properly include demangling, assertions and werror?

 

Sorry for the late reply here. I was having trouble building a project and interfacing it with calls to page JavaScript. I have however gotten past this problem. I was asking mainly because I could add one define using the method you listed above but not all three (Demangle, Assertions and Werror).

 

Ok I see now. Thank you for clearing that up.

 

On a related note: how can one set the WebGL exception handling level in an editor script?

 

Thanks Jonas!

Small correction for the record...

You need to swap the last two arguments:

PlayerSettings.SetPropertyInt("exceptionSupport", i, BuildTargetGroup.WebGL);

 

Getting off-topic, but out of curiosity:

- exceptionSupport 0 ('None') sets the emcc flag DISABLE_EXCEPTION_CATCHING=1

- exceptionSupport 1 ('Explicitly Thrown Exceptions Only') and
- exceptionSupport 2 ('Full')
both set the emcc flag DISABLE_EXCEPTION_CATCHING=0

I couldn't find a difference between the latter two in the emcc flags. So what causes the difference in error reporting?