C\ProgramFiles\EpicGames\UE_5.6\Engine\Source\Runtime\CoreUObject\Public\UObject\UObjectGlobals.h(738,33): error C3615: function constexpr ‘FLoadPackageAsyncProgressDelegate::BuildMask’ cannot contain const expression
chatGPT told me it was about MSCV 14.38 which didn’t support some c++20 new feature …
so i managed to generate my .uproject with last version MSCV 14.44 … by rebuilding UnrealBuildTool.dll, bypassing the exception that blocks versions 14.39+
But i still got the compiling error.
chatGPT made me verify eveything, .NET installs, right compiler version etc … but ended up (after 6 hours) telling me it was pointless unless i recompile the unreal myself … which i don’t want to do.
Has anyone successfully compiled a 5.6 project?
I find it weird that noone else has this, even with fresh installs (UE + VS2022)
well in 5.6, c++ version goes from v17 to v20, and there is quite some changes.
i solved it by adding this line in ''ProjectNameEditor.target.cs":
WindowsPlatform.bStrictConformanceMode = true;
I encountered this issue, and it ended up being this GooglePlay plugin (GitHub - google/play-unreal-engine-plugin) I added to my project. In it’s build.cs files it was setting Cpp to 17. Once I changed that to Cpp 20 my problem was solved.
Possibly relevant, the solution I ended up with was to include every version of SDK/MFC/ATL that is not specific to a custom solution. If it said (x86 & x64) and was not specific to a custom package, I checked all of them. And that layer of build problems went away.
If you have time, please see my latest post for the next round of problems that I ran into, that I still do not have solutions for. Thanks, Tim
