[MACOS/XCODE] - Editor fails compiling bc Unused Variables

Hi,
I’ve been working on a project for several weeks now. I stopped development just a few days and now C++ projects fails compiling when Editor configuration is set. I cannot open the Editor either! It gives me the following error:

Captura de pantalla 2022-04-09 a las 9.57.46

When clicking in “YES”, it tries to compile the code, resulting in following error:

Running Mono...

Found mono via known Mono.framework path
Running system mono/msbuild, version: Mono JIT compiler version 6.12.0.122 (2020-02/c621c35ffa0 Wed Feb 10 00:51:43 EST 2021)
/Users/Shared/EpicGames/UE_4.27/Engine /Users/Shared/EpicGames/UE_4.27/Engine/Binaries/Mac
Creating makefile for TestErrorEditor (no existing makefile)
@progress push 5%
Parsing headers for TestErrorEditor
  Running UnrealHeaderTool "/Users/mariano/Documents/UnrealProjects/TestError/TestError.uproject" "/Users/mariano/Documents/UnrealProjects/TestError/Intermediate/Build/Mac/x86_64/TestErrorEditor/Development/TestErrorEditor.uhtmanifest" -LogCmds="loginit warning, logexit warning, logdatabase error" -Unattended -WarningsAsErrors -abslog="/Users/mariano/Library/Application Support/Epic/UnrealBuildTool/Log_UHT.txt" -installed
2022-04-09 09:42:33.284 UnrealHeaderTool[68914:10264051] [UE4] Looking for binary: ../../../Engine/Programs/UnrealHeaderTool/Config/BinaryConfig.ini
LogInit: Display: Loading text-based GConfig....
Reflection code generated for TestErrorEditor in 4,5260797 seconds
@progress pop
Building TestErrorEditor...
Performing 7 actions (10 in parallel)
[1/7] Compile SharedPCH.Engine.ShadowErrors.h
In file included from /Users/mariano/Documents/UnrealProjects/TestError/Intermediate/Build/Mac/x86_64/TestErrorEditor/Development/Engine/SharedPCH.Engine.ShadowErrors.h:284:
In file included from /Users/Shared/EpicGames/UE_4.27/Engine/Source/Runtime/Engine/Public/EngineSharedPCH.h:572:
/Users/Shared/EpicGames/UE_4.27/Engine/Source/Runtime/Engine/Classes/Materials/Material.h:1279:26: error: variable 'LayerNames' set but not used [-Werror,-Wunused-but-set-variable]
                                const TArray<FText>* LayerNames = &LayersExpression->GetLayerNames();
                                                     ^
1 error generated.

I think the issue was Apple updating XCode on late march to 13.3 version… but i’m not sure about it.

I tried to modify LLVM’s warnings flags on XCode, without any results. Looks like compiler is ignoring it.

Captura de pantalla 2022-04-09 a las 9.46.24

When I compile the code using the “Without Editor” setup, it compiles just fine…

Running system mono/msbuild, version: Mono JIT compiler version 6.12.0.122 (2020-02/c621c35ffa0 Wed Feb 10 00:51:43 EST 2021)
Running Engine/Binaries/DotNET/UnrealBuildTool.exe TestError Mac Development /Users/mariano/Documents/UnrealProjects/TestError/TestError.uproject
Creating makefile for TestError (no existing makefile)
Couldn't find PLCrashReporter in folder 'lib-Xcode-13.3', using default 'lib-Xcode-12.4'
Parsing headers for TestError
  Running UnrealHeaderTool "/Users/mariano/Documents/UnrealProjects/TestError/TestError.uproject" "/Users/mariano/Documents/UnrealProjects/TestError/Intermediate/Build/Mac/x86_64/TestError/Development/TestError.uhtmanifest" -LogCmds="loginit warning, logexit warning, logdatabase error" -Unattended -WarningsAsErrors -abslog="/Users/mariano/Library/Application Support/Epic/UnrealBuildTool/Log_UHT.txt" -installed
LogInit: Display: Loading text-based GConfig....
Reflection code generated for TestError in 3,0606982 seconds
Building TestError...
Performing 11 actions (10 in parallel)
[1/11] Compile SharedPCH.Engine.ShadowErrors.h
[2/11] Compile TestErrorGameModeBase.cpp
[3/11] Compile TestError.init.gen.cpp
[5/11] Compile TestErrorGameModeBase.gen.cpp
[4/11] Compile TestError.cpp
[6/11] Link TestError
Generating TestError.dSYM
Copying RadioEffectUnit.component to app bundle
Fixing dylib dependencies for TestError
Finalizing app bundle: TestError.app
[11/11] UnrealBuildTool.exe TestError.target
Total time in Local executor: 21,15 seconds
Deploying TestError Mac Development...
Deploying now!
Total execution time: 28,64 seconds
Build succeeded at 9:53:44 

But when launched, it throughs same initial error.

My setup:

  • macOS Monterey 12.1
  • Unreal Engine 4.27.2
  • XCode 13.3
  • I’m using also JetBrains Rider 2022.1 EAP 9 for manual compiling, but it uses macOS LLVM.
  • Apple clang version 13.1.6 (clang-1316.0.21.2)

Any help will be very appreciated. Right now I’m stuck and without further ideas…

Thanks in advance. Best,

1 Like

Ok, I was right: XCode version 13.3 breaks compatibility with UE4.27.2.
I reinstalled previous version (13.2.1) and everything worked.

2 Likes

it also breaks UE5…

But eventually, UE5 should add comptiable on xcode 13.3