Cloud Build issue: Android: Shader error in 'Sprites/Default': Internal error communicating?

Unity Services
1

Here are the part of the logs:

[Unity] Shader compiler: exception while compiling shader snippet. Thread=-1162697792 Type=0 platform=5. Source:
[Unity] #line 30 “”
[Unity] #ifdef DUMMY_PREPROCESSOR_TO_WORK_AROUND_HLSL_COMPILER_LINE_HANDLING
[Unity] #endif
[Unity] #include “HLSLSupport.cginc”
[Unity] #include “UnityShaderVariables.cginc”
[Unity] #include “UnityShaderUtilities.cginc”
[Unity] #line 30 “”
[Unity] #ifdef DUMMY_PREPROCESSOR_TO_WORK_AROUND_HLSL_COMPILER_LINE_HANDLING
[Unity] #endif
[Unity] /* UNITY: Original start of shader */
[Unity] #pragma vertex SpriteVert
[Unity] #pragma fragment SpriteFrag
[Unity] #pragma target 2.0
[Unity] #pragma multi_compile_instancing
[Unity] #pragma multi_compile _ PIXELSNAP_ON
[Unity] #pragma multi_compile _ ETC1_EXTERNAL_ALPHA
[Unity] #include “UnitySprites.cginc”
[Unity] Shader compiler: internal error compiling shader snippet type=0 platform=5: Protocol error - failed to read correct magic number
[Unity] UnityEditor.BuildPipeline:BuildPlayerInternalNoCheck(String[ ], String, String, BuildTargetGroup, BuildTarget, BuildOptions, Boolean)
[Unity] UnityEditor.CloudBuild.Builder:Build()
[Unity] Shader compiler: UnityShaderCompiler compiler executable disappeared on thread -1162697792, restarting
[Unity] Launched and connected shader compiler UnityShaderCompiler after 0.07 seconds
[Unity] Compiled shader ‘Sprites/Default’ in 2.75s
[Unity] gles (total internal programs: 23, unique: 8)
[Unity] gles3 (total internal programs: 24, unique: 8)
[Unity] vulkan (total internal programs: 24, unique: 8)
[Unity] Shader error in ‘Sprites/Default’: Internal error communicating with the shader compiler process
[Unity] (Filename: Sprites/Default Line: -1)

[Unity] Player export failed. Reason: Shader error in ‘Sprites/Default’: Internal error communicating with the shader compiler process

This happens often when building for Android. Sometimes it happens, sometimes not. And this issue has been existing for a long time. What can we do to prevent it? or it is just unfixable?

2

Now it happens on iOS too. What’s going on?

3

That is a sporadic error (a crash) that the Unity Shader compiler process can experience, and we’ve found that the Cloud Build environment can run into more often than most people’s local computers. The Cloud Build team are actively working with the graphics teams on a permanent fix for this, and are seeing some promising internal test results now - in the meantime, this error is rare overall but tends to recur for certain projects/shaders (making it very frustrating if you have an affected project, we know). If you rebuild a few times it should eventually succeed.