Silent 5.5 assert/crash in UnrealBuildAccelerator when trying to run dump_syms.exe for Linux build. Fixed in 5.6?

Development Pipeline & Plugins
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Hello!

We’ve been trying to track down a issue where our Linux server crash reports were reporting non-sensical callstacks. We narrowed it down to stale .psym/.sym files on our build machines.

When digging into the issue, we discovered that the Link-OnyxServer-Linux-Test.link.bat script was failing, specifically when attempting to run dump_syms.exe (to produce the .psym file).

We noted that we could run dump_syms.exe manually and it succeeded no problem. After modifying LinuxToolChain.cs/LinuxToolChain::GetDumpEncodeDebugCommand()/Link-OnyxServer-Linux-Test.link.bat to not quiet error logging we were able to see the above assert/crash.

We were able to work around this by disabling UBA via bAllowUBAExecutor/bAllowUBALocalExecutor. We also were able to workaround this by using the 5.6 UBA binaries instead.

So I guess my question here is: Is it safe to utilize all the 5.6 UBA binaries with 5.5? UBA is a little bit of a blackbox to me, and I am just wanting to be sure I’m not introducing potential other issues.

As you can probably tell (from the .bat/.exe references), we’re building from Windows for Linux.

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Steps to Reproduce
For us, it’s as simple as building our project for “Test Server” on Linux (after properly setting up the appropriate cross-compile toolchain, etc.)

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Hi Mike,

yes it should be safe to take as new uba as possible. I am really trying to keep it backwards compatible and fixes/improvements are constantly flowing in.

Inside Epic we are currently having huge problems with memory on our build machines (Fortnite is a beast).. so there has been quite a lot of opts related to memory and especially when having compressed obj files enabled