UBT failing after successful compile/hot-reload

I’m having some annoying compile issues that seem very strange with 4.15 and VS15 update 2. Here are the facts:

  1. I can successfully compile a clean build in VS15 with no errors
  2. If I compile in VS a second time, UE4 says “Hot Reload successful” but VS reports the build failing as seen below
  3. If I compile in UE4, it succeeds with no error
  4. If I compile in UE4 (and it succeeds), and then make changes and compile in VS, it succeeds even without cleaning. If I compile a second time in a row in VS it fails again, as it did before.

2> Creating library C:\sh_js\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-RG2-20.lib and object C:\sh_js\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-RG2-20.exp

2> Creating library C:\sh_js\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-RG2-20.suppressed.lib and object C:\sh_js\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-RG2-20.suppressed.exp

2>ERROR : UBT error : Failed to produce item: C:\sh_js\Intermediate\Build\Win64\UE4Editor\Development\UE4Editor-RG2-743.lib

This is the only error and this is the entire description it gives. So basically it succeeds every time except for the second time I try to compile in VS in a row - and even then, it seems like it succeeds but VS is giving me an error. What seems weird the .lib that’s failing has a different number than the one that succeeds (20.lib vs 743.lib), and I thought it was only supposed to generate 1 set of files. When it succeeds, I get the following message instead of the error (and there’s no mention of a second .lib file anywhere in the log when it succeeds):

2> Deploying RG2Editor Win64 Development...

I also experience the same issue however if I “Rebuild” it is successful with no warnings. (but takes a lot longer).

Also running 4.15.

This was fixed in 4.15.1!

Thanks, Epic