UE4 Editor stops reloading C++ code after some time

If i Open editor, then open Visual Studio project from editor, and then Build my project - then i see - Hot-Reload is complete popup message, and everything is fine.

But after some time for unknown reason there is no more popup message, and my changes to code does not refleted in editor. Even if i close Visual Studio and then reopen it from editor again - this does not work. I have to close Editor completely, and close Visual Studio completely, and then reopen editor, to make hot-reload work again.

This happens to me all the time, every time.

When i reopen editor, it ask me to rebuild MyProject.dll, because it is outdated or smth.

Hello newbprofi,

I’ve seen this issue a few times myself but been working on finding a concrete reproduction case as that would be needed to get a good grasp on the issue itself. I’m curious though, whenever this happens and the code is no longer being taken into account, does the “Compile” button disappear from the top of the UE4 Level Editor, as if you were using a Blueprint only project? In the past, it seems to be related to failed compiles. I’ll continue looking into what exactly causes it but if you can provide any additional detail, that would be helpful.

Hello newbprofi,

A fix related to this issue went in for 4.12’s release. Have you been able to give 4.12 a try yet to see if the issue is still occurring there for you?

I entered another bug in today for a related problem but it seems to be only upon failing to hot reload and on in particular circumstances. It shouldn’t affect you, but let me know if you start seeing this occur more often when failing to compile something and maybe we can get some more information on that.

We haven’t heard from you in a while, newbprofi. Have you been able to try what I mentioned in my previous comments? If so, please let me know the results. In the meantime, I’ll be marking this as resolved for tracking purposes.