Nizami_Nz
April 26, 2025, 8:57pm
1
Continuing the discussion from Can't compile 5.4 Projects anymore, I need help. :
So a while back I started getting this message from the engine whenever I tried creating a new project in unreal engine 5.4.
C:\Program Files\Epic Games\UE_5.4\Engine\Source\Runtime\Core\Public\Experimental\ConcurrentLinearAllocator.h(31): error C4668: ‘__has_feature’ is not defined as a preprocessor macro, replacing with ‘0’ for ‘#if /#elif ’
I’m not sure what the message was about since it seemed to do with code I haven’t touched. This all started happening after I tried to update my tool chain (vs and rider). Fine. Maybe I messed that up. Fast forward after days of trying to get my set up back to a working state I decide to reinstall everything. (Rider VS and Unreal.) no dice. So I wipe my entire pc and reinstall everything. I thought for sure that would be the silver bullet since that would set me back to square one, but alas when I opened up UE5.4 this morning and tried to create a new project I got this message again.
I’m really at a loss here. I know it’s gonna be something silly like a check box I need to hit, but can someone please help me? I don’t know what to do anymore. I’ve tried asking chat, but it doesn’t give any helpful advice.
For those who are looking for an answer !
The solutions above were partially correct:
Open file in your project (ProjectFolder → Source → project.target.cs)
Open file in folder (AppData\Roaming\Unreal Engine\UnrealBuildTool) and change code with new version:
Code:
<?xml version="1.0" encoding="utf-8" ?>
<Configuration xmlns="https://www.unrealengine.com/BuildConfiguration">
<WindowsPlatform>
<CompilerVersion>14.38.33130</CompilerVersion>
</WindowsPlatform>
</Configuration>
Important, when I first changed the file to new version, I got an error that there was no such version (MSVC).
But (Unreal Engine) also wrote what version is present in (Visual studio), so I just changed the version in code to the one that was already on the computer.
Done!
