Troubleshooting

Build Issues

Linker Errors After Plugin Update

When updating the Sentry plugin by copying new files over an existing installation, leftover files from the previous version can cause linker errors like:

LNK2001: unresolved external symbol

This happens when source files that were removed in a newer version of the plugin remain in your project directory. UBT compiles them, but the symbols they reference no longer exist.

Solution

Delete the entire Sentry plugin folder before copying the new version:

rm -rf Plugins/sentry-unreal

Then copy the new plugin files into place. Simply overwriting files won't remove sources that were deleted upstream.

Perforce: Stale Binaries on Build Machines

When using the Sentry Unreal SDK with Perforce, updated binaries from the plugin's ThirdParty directory may not be copied into the Binaries directory during the build. This can result in outdated Crashpad or Sentry binaries being used at runtime.

Cause

Unreal Build Tool (UBT) determines whether to copy files based on file modification timestamps. A file is only copied if the source is newer than the destination.

If your Perforce depot stores binaries with the +m (modtime) typemap attribute, synced files retain their original submission timestamps rather than receiving the current time. On CI or build machines where Binaries already contains a previous version of these files (for example, from a VM image or earlier build), the existing files may have newer timestamps than the freshly synced ThirdParty sources. UBT then skips the copy, assuming the existing binaries are up to date.

Symptoms

• Sentry fails to initialize on build machines but works locally
• Old versions of crashpad_handler.exe or crashpad_wer.dll are used at runtime
• Plugin updates appear to have no effect on packaged builds

Solutions

You can resolve this with any of the following approaches:

• Remove the +m attribute from binary files in Perforce. This ensures synced files receive the current timestamp and are treated as newer by UBT.
• Clean the plugin's Binaries directory before building.
• Avoid pre-populating Binaries in VM or build machine images. Ensure that build environments don't carry over stale binaries from previous SDK versions.