[4.22] Compilation Triggers UnrealHeaderTool even only one .cpp file changed

After migrating to 4.22 I notice that the reflection code generation take a big chunk of the compilation time.

Before 4.22 the UHT only runs when there are changes in header files, but now every tiny change in .cpp seems to invoke UHT.

Is there any setting I miss? Or this is intentional in 4.22?

I’m seeing the same thing… while this is not a big problem on my workstation (UHT takes 5s there for my project) the same project needs up to 60s for the reflection code on my laptop (with an i7 @ 2.8Ghz), which is a steep increase from before…

Yeah I’m generally experiencing the same thing, which is strange considering the release notes outlined how this area saw huge speed increases.

Just curious, are you guys using VS 2019 or 2017?

Apparently there is a bug in 4.22 where if you use a launcher build, UHT runs every time.

Has anyone reported this yet?

Sorry I had hard time tracking my post in this forum.

I had reported the issue to EPIC support. Here’s the link: Unreal Engine Issues and Bug Tracker (UE-74102)

Please vote if you have encountered the issue too.

It seems that if you build the engine from Github it won’t have this problem, but I haven’t tested it personally.