[Bug][Linux][4.11] Building lighting fails with missing lib message

Error building lighting, it exports everything fine but running UnrealLightmass fails with this message. This is the latest from github.

/mnt/store/UnrealEngine/release/Engine/Binaries/Linux/UnrealLightmass: error while loading shared libraries: libUnrealLightmass-Serialization.so: cannot open shared object file: No such file or directory

UnrealLightmass can not find the missing lib

Engine/Binaries/Linux $ ldd UnrealLightmass | grep not
        libUnrealLightmass-Serialization.so => not found

But it is locatedi in the same folder as UE4Editor and UnrealLightmass

Engine/Binaries/Linux $ ls libUnrealLightmass-* | grep Serial

libUnrealLightmass-Serialization.so RUNPATH

Engine/Binaries/Linux $ readelf --dynamic libUnrealLightmass-Serialization.so | grep PATH
 0x000000000000001d (RUNPATH)            Library runpath: [${ORIGIN}:${ORIGIN}/../../../Engine/Binaries/Linux:${ORIGIN}/..:${ORIGIN}/../../../Engine/Binaries/ThirdParty/ICU/icu4c-53_1/Linux/x86_64-unknown-linux-gnu:${ORIGIN}/../../../Engine/Binaries/ThirdParty/LinuxNativeDialogs/Linux/x86_64-unknown-linux-gnu]

UnrealLightmass RUNPATH

Engine/Binaries/Linux $ readelf --dynamic UnrealLightmass | grep PATH
 0x000000000000001d (RUNPATH)            Library runpath: [${ORIGIN}:${ORIGIN}/../../../Engine/Binaries/Linux:${ORIGIN}/..:${ORIGIN}/../../../Engine/Binaries/ThirdParty/ICU/icu4c-53_1/Linux/x86_64-unknown-linux-gnu:${ORIGIN}/../../../Engine/Binaries/ThirdParty/LinuxNativeDialogs/Linux/x86_64-unknown-linux-gnu:${ORIGIN}/../../Plugins/Messaging/UdpMessaging/Binaries/Linux]


Engine/Binaries/Linux $ readelf --dynamic UE4Editor | grep PATH
 0x000000000000001d (RUNPATH)            Library runpath: [${ORIGIN}:${ORIGIN}/../../../Engine/Binaries/Linux:${ORIGIN}/..:${ORIGIN}/../../../Engine/Binaries/ThirdParty/ICU/icu4c-53_1/Linux/x86_64-unknown-linux-gnu:${ORIGIN}/../../../Engine/Binaries/ThirdParty/LinuxNativeDialogs/Linux/x86_64-unknown-linux-gnu]

Have to start the editor with

LD_LIBRARY_PATH=":.:" ./UE4Editor "/path/to/Unreal Projects/SomeProject/SomeProject.uproject" 

in-order to rebuild lighting “/path/to/Unreal Projects/SomeProject/SomeProject.uproject” being the direct path to your projects uproject file, else if your loaded the project from the project browser and the editor restarts you may not get the system var override passed onto the next UE4Editor process.

Hey -

I was able to open a new project and build lighting successfully. Are you seeing this in a new project? Is there anything other then using the Build button in the toolbar? Did you run “make UnrealLightmass” when building the engine initially? Also, you mentioned having to open the project in a specific way as a workaround, how are you opening the project when this issue occurs?


It may be a gentoo specific issue, there may be another distro with the same issue as it happened before with other UE4 apps on two distros, gentoo and a second distro (I can’t remember the name atm, it may be centos or opensuse).

if I run it with LD_LIBRARY_PATH=":.:" it works, without it it fails with the missing lib. it also/probably is an issue with that specific libs linking. I build UnrealLightmass with make which builds them all the defaults at one time.

Hey -

Thank you for the information. Using this I have entered a report about the lighting failing to build (UE-25522) for further investigation.


I can confirm to have this issue I am in Fedora, it must just be some “make file” update only, hows in Ubuntu?

Ok, It seams I found a solution, do this two times

make UnrealLightmass

and it will generate all the required libraries, Build Lighting now works in a heartbeat.

UnrealEngine 4.12.3 & Fedora 21 to be specific