4.6 Preview Mac Issue

Evening wonderful folks. I love what you’ve done in the 4.6 preview !
I built it on Windows and everything runs pretty well considering its a preview. I wanted to test the multiplayer stuff that you guys have put so much work into. I don’t have two PC workstations to test this through steam(using my own appid) but I do have an iMac handy. I’ve built the engine on it before so that part went smoothly.

The problem comes in when I start the editor (or my custom game project that I brought over) in debug mode. At a certain point in the startup process, I get kicked back to XCode with the following breakpoint around line 52 of MacPlatformMisc.h.

ShaderCompilingThread(16): EXC_BREAKPOINT(code=EXC1386_BPT,subcode=0x0)

I’ve included the log below for your reference.

[Output Log]

I’d love to be able to get an updated Mac version of my game build for my Steam store :slight_smile:
I would be most appreciative for any help with this.

Best Regards and Much Love


Hi MrNexy,

I assume that you’ve installed all the required binaries correctly and that the ShaderCompileWorker is present in the UE4/Engine/Binaries/Mac folder, along with all its dependent dylibs?

These are:
• ShaderCompileWorker
• ShaderCompileWorker-Core.dylib
• ShaderCompileWorker-DesktopPlatform-Mac-Debug.dylib
• ShaderCompileWorker-DesktopPlatform.dylib
• ShaderCompileWorker-ImageCore.dylib
• ShaderCompileWorker-ImageWrapper.dylib
• ShaderCompileWorker-Json.dylib
• ShaderCompileWorker-MetalShaderFormat.dylib
• ShaderCompileWorker-Projects-Mac-Debug.dylib
• ShaderCompileWorker-Projects.dylib
• ShaderCompileWorker-RenderCore.dylib
• ShaderCompileWorker-RHI.dylib
• ShaderCompileWorker-SandboxFile.dylib
• ShaderCompileWorker-ShaderCompilerCommon.dylib
• ShaderCompileWorker-ShaderCore.dylib
• ShaderCompileWorker-ShaderFormatOpenGL.dylib
• ShaderCompileWorker-ShaderPreprocessor.dylib
• ShaderCompileWorker-TargetPlatform.dylib
• ShaderCompileWorker-TextureFormatPVR.dylib

The error in the logs is saying that the ShaderCompileWorker can’t launch because one of the dylibs cannot be loaded - usually this means it can’t be found or has been corrupted.

Running “otool -L /Path/To/UE4/Engine/Binaries/Mac/ShaderCompileWorker” (where /Path/To is replaced by the actual path on your Mac to the UE4 folder) will tell you the link order for ShaderCompileWorker from which dylib #9 isn’t working. The most likely cause is that you haven’t got all the required binaries unpacked to the right place for some reason - you could try building the ShaderCompileWorker yourself to see if that resolves the problem.

As for the crash - it is an assert checking for execution on the game thread, somehow it isn’t. I’ll need the crash log folder from UE4/Engine/Saved/Crashes to investigate that.

Its been a crazy busy past couple weeks on my end, I do apologize for not responding sooner.

I re-attempted building the engine on Mac from source after the release of 4.6. The issue persists even after having followed the build instructions as per the GitHub release notes. Dependencies are downloaded using Setup.

However when I use the pre-built version it I have no issues. I recently upgraded to Yosemite and repeated the whole setup process but the results are the same.

The problem is actually with the binaries supplied in the Github source release. We have fixed the problem upstream. For now you’ll either need to use the binaries from the binary build OR rebuild the ShaderCompileWorker/UnrealPak/UnrealLightmass etc. from your GitHub Xcode project (you’ll want to select the target from the scheme drop-down and build for Profiling). Apologies.

No worries.
Thanks for the info , I will give it a go.Thank you for getting back to me.