Bug What is the correct way to use .a static libraries in webgl? getting runtime errors

Hi, i need someones help. The problem is:
I am trying to use .a library in my project. it is SkiaSharp, that works ok on mac, android, ios, windows. And it has wasm support, but I cant make it work in unity web builds. When I use C# wrapper I get errors:

First one:
test.loader.js:1 To use dlopen, you need to use Emscripten's linking support, see https://github.com/kripken/emscripten/wiki/Linking

and

test.framework.js.gz:2 DllNotFoundException: Unable to load DLL 'libSkiaSharp': The specified module could not be found.
at SkiaSharp.SkiaApi.sk_colortype_get_default_8888 () [0x00000] in <00000000000000000000000000000000>:0
at SkiaSharp.SKImageInfo..cctor () [0x00000] in <00000000000000000000000000000000>:0
at SkiaSharp.SKBitmap..ctor (System.Int32 width, System.Int32 height, System.Boolean isOpaque) [0x00000] in <00000000000000000000000000000000>:0
at Test.Start () [0x00000] in <00000000000000000000000000000000>:0
Rethrow as TypeInitializationException: The type initializer for 'SkiaSharp.SKImageInfo' threw an exception.
at SkiaSharp.SKBitmap..ctor (System.Int32 width, System.Int32 height, System.Boolean isOpaque) [0x00000] in <00000000000000000000000000000000>:0
at Test.Start () [0x00000] in <00000000000000000000000000000000>:0

But I have libSkiaSgarp.a library built for wasm, and it works for Uno Platform, but does not for unity.
Maybe I am doing something wrong?

 

having the same issue here

 

As shown in the manual, in Unity WebGL you need to use [DllImport("__Internal")] and not the lib/file name.
https://docs.unity3d.com/Manual/webgl-interactingwithbrowserscripting.html

 

Thank you, I tried to use __Internal, but now i get

"wasm-ld: error: duplicate symbol" errors

 

Code (CSharp):

1. Building Library/Bee/artifacts/WebGL/build/debug_WebGL_wasm/build.js failed with output:
2. wasm-ld: error: duplicate symbol: jsimd_can_rgb_ycc
3. >>> defined in /var/folders/18/99jndmds6px_w52xph7yfc_h0000gn/T/tmpo_khbkvaWebGLSupport_ImageConversionModule_Dynamic.a(External_libjpeg-turbo_src_0_j00uw.o)
4. >>> defined in Assets/Scenes/Plugins/WebGL/libSkiaSharp.a(libjpeg.jsimd_none.o)
5.  

 

I think that the problem is duplicate of same library (libjpeg) inside libSkiaSharp.a and Unity3d, but I cant find the way how to solve it

 

I fixed duplicate errors, the solution was to rebuild libjpeg, libpng and freetype with rename of some of their methods. Now I've got new pack of errors

https://forum.unity.com/threads/mayby-mangling-error-when-trying-to-link-a-library.1191196/

 

First I had problems with libjpg and libpng, conflicting names. So I Created some regex functions and remaned them everywhere in skia (jsimd functions and etc)

Then I had problems on Linking:
Library/Bee/artifacts/WebGL/build/debug_WebGL_wasm/build.js: undefined symbol: _ZNSt3__212basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEE17__assign_externalEPKcm (referenced by top-level compiled C/C++ code)
UnityEditor.BuildPlayerWindow:BuildPlayerAndRun () (at /Users/bokken/buildslave/unity/build/Editor/Mono/BuildPlayerWindow.cs:179)

The reason was my emscripten version (2.0.32),So I downgraded to 2.0.19 (same as Unity 2021.2) and installed Ubuntu 2.0.4 (cause 2.0.19 does not exist for my mac)

Now it compiles. But I get runtime errors:

Code (CSharp):

1.  
2. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[35775]:0xa659b0
3. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3667]:0x122e5f
4. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3668]:0x122f78
5. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[9093]:0x34de83
6. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[35429]:0xa3fcfe
7. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[16989]:0x632db5
8. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[2786]:0xcab5e
9. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[16979]:0x63298d
10. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[20165]:0x782c31
11. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[26785]:0x923f3b
12. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[5737]:0x20ca83
13. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[21613]:0x7a9dd7
14. at invoke_iiii (http://localhost:49782/Build/skia.framework.js:2:389202)
15. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[1390]:0x5c05a
16. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3848]:0x13a31c
17. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[687]:0x25741
18. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[34354]:0xa2350d
19. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[26785]:0x923f3b
20. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[5737]:0x20ca83
21. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[21613]:0x7a9dd7
22. at invoke_iiii (http://localhost:49782/Build/skia.framework.js:2:389202)
23. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[1390]:0x5c05a
24. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3848]:0x13a31c
25. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[687]:0x25741
26. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[12641]:0x55cc09
27. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3866]:0x13acb1
28. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[12823]:0x5620be
29. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3001]:0xe3a28
30. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[28620]:0x945350
31. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[27463]:0x92f9a0
32. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[5737]:0x20ca83
33. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[21613]:0x7a9dd7
34. at invoke_iiii (http://localhost:49782/Build/skia.framework.js:2:389202)
35. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[1390]:0x5c05a
36. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[17433]:0x67009c
37. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[959]:0x32eb5
38. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[3326]:0x106663
39. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[25951]:0x8f772c
40. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[24919]:0x89d6b6
41. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[23583]:0x7ecc60
42. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[12154]:0x54768f
43. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[12154]:0x5476fe
44. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[10676]:0x458824
45. at http://localhost:49782/Build/skia.wasm.gz:wasm-function[21608]:0x7a9d99
46. at browserIterationFunc (http://localhost:49782/Build/skia.framework.js:2:257698)
47. at callUserCallback (http://localhost:49782/Build/skia.framework.js:2:131767)
48. at Object.runIter (http://localhost:49782/Build/skia.framework.js:2:133027)
49. at Browser_mainLoop_runner (http://localhost:49782/Build/skia.framework.js:2:131302)

 

I dont know what to do with it yet. but I am surprised to see skia.was.gz here, cause I do not use gz compression in Unity for now. Can it be a bug?

 

An abnormal situation has occurred: the PlayerLoop internal function has been called recursively. Please contact Customer Support with a sample project so that we can reproduce the problem and troubleshoot it.

 

I found out that it does not fail on development build, and fails on dev build off. I start thinkng there can be a bug. I will investigate this problem and create a reproductable test to make sure

 

I don't know what is your use case, but maybe you should try and work with 2 WASM files,
one for unity, one for the external lib.
and just share between them the end result.
It may help you later in case you need large amount of memory

 

Very interesting idea, I will investigate it too, but first I will try to check if native lib can be called from C# all inside unity without implementing 2 wasm programs

 

So I made it to work in development build. Now I will try investigate if there is a bug and will provide reproduction project

 

So development build works, and non development does not. I will start the new thread and prepare the repo with repro