Engine always rebuilding on the project build

I’m using the 4.4.3-release tag version from the github. Have built is successfully. Have then ran UnrealVersionSelector-Win64-Shipping.exe. As next I’ve generated the solution files for my project. I’ve opened the solution in VS. If hit build (the project-only or not - it doesn’t matter) the whole engine is starting rebuilding. When I switch to the version installed from installer, everything is working great. Also when using the custom-built version, in my project solution, there I have also the engine project there. When using the installer version, only my project is in the solution (when opened in the VS).
If I reopen the main engine solution and hit rebuilt, nothing is rebuilt. All stuff is up-to-date.

Could anybody tell me how to stop the engine rebuilding on project build? I’ve tried to find some solution to my problem but nothing has worked for me.

I’m using VS 2013 pro, Unreal Engine 4.4.3-release tag (f239e891d8bc801165989f70c150d7625945a9bc) on home x64.

offtopic: Using the dots “.” in the git tags an branches is discouraged AFAIK.

Thanks

Hey Trigve,

I’m cleaning up old issues - are you still having this problem?

I haven’t tried it recently as I’m not using UE now.

Hi,

just to share my 2 cents.
I also had this issue and the solution was to ensure in the solution properties that the starting project is your project name and not UE4.

I have same issue.

Rebuilding only project or just rebuilding - doesn’t matter. It alwayt rebuilds Engine and project together.

Startup project is seted to my, not to UE4.

Doesn’t work.

Hey Alanir,

So you’re saying that whenever you create and compile a code project (presumably using the Source version of the engine from Github) in 4.4.3, visual studio compiles both the project and the engine, wasting a lot of time.

Is that correct?

No. UE 4.6.1 builded from source. When I’m trying to rebuild only my project, it rebuilds whole engine.

I’m still not able to reproduce this in 4.6.1. Here are the steps I’m following.

  1. With the editor open, File->New Project
  2. Code tab->Basic Code (No Starter Content)
  3. Click “Yes” to open the project in visual studio.
  4. Right click on project name in the Solution Explorer, then click ‘Build’ from that menu.
  5. At some point in the future, right click on the project name in the Solution Explorer and then click ‘Rebuild’ from that menu.

Is there something you’re doing that I’m not?

Click not “Build”, but “Rebuild”.

I’m trying to REbuild ONLY my project.

I was mistaken before. Rebuild is intended to clean and build everything - both the project and the engine. If you only want your project to build, you should be using the ‘Build’ option. I’m sorry for any confusion.

Hi! I have the same problem.

: It seems misleading to have an option Build => Project Only => Clean Only “ProjectName” which does not clean only the project (game) but the engine also.

I really need an option to clean only the level code. I am trying to include some dll and somehow that throws of the whole build process when I include a class from that library into my code. I get an error about a missing root in an xml file. After that, even if I don’t include that class anymore, building will fail until I clean the project. Which means also cleaning the engine. Bad.

A clean project only option would be nice here.

Hi mreese,

The option you are referring to (Build → Project Only → Clean Only “ProjectName”) is a Visual Studio option, not one that is exclusive to Unreal Engine 4. What actually happens when a Project Only Clean process is begun, is that Visual Studio not only cleans the Project, but it also checks to see if it is able to clean anything that the Project depends on. Since you are using a version of the Engine that is built from source code, Visual Studio includes that dependency in the Clean process, which ends up requiring a full build of the Engine. The same occurs if you attempt to rebuild the project only.

If you wish to be able to perform a clean at only the project level, you would need to navigate to where your project is located in a Windows Explorer window.

  • In the root project folder, delete the Binaries, Build, DerivedDataCache, and Intermediate folders.
  • Right-click on the project’s .uproject file and select the Generate Visual Studio project files option (this will recreate the Intermediate folder).
  • Open the project solution in Visual Studio and Build the project (this will recreate the Binaries and Build folders).
  • When the build completes in Visual Studio, double-click the project’s .uproject file to open it in the Editor (this will recreate the DerivedDataCache folder).

You should now have a “Clean” project without needing to rebuild the Engine.

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Hi , thanks for the detailed advice. I’ll try your procedure next time it comes up.

Cheers!

Wow thanks for the info. This is insanely unstreamlined though. Nothing “just works” with unreal c++ development T_T

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Thank you for your response I was building the engine every time too lol

Hi.I also have the same problem. Right Click you project,Only rebuild you project may work.
I don’t wanna rebuild the UE4 ever again in my life if I don’t change it.

same here with 4.26.1

Same here with 4.27.2. Annoying. Did rebuilt the engine many times now for now reason. The project doesn’t open anyway. When I try, it says:
ERROR: Building would modify the following engine files:

My start project is set as my project and not UE4 engine. I also did manual builds of the project, where I clean folders manually.

Ok, I got it solved by rebuilding once again, right after it gives the error of ERROR: Building would modify the following engine files:". I just opened visual studio and pressed built. Did not delete the folders this time.