Issues updating to Xcode 26 -- can no longer successfully build project

I recently updated to macOS sequoia 15.6

Afterward, I updated to Xcode 26

The project I've been running for the last couple years no longer compiles on existing simulators and doesn't build to a physical device. I'm getting an error I'm not familiar with and have no idea how to directly resolve it:

The specific error is 'Command SwiftGeneratePch failed with a nonzero exit code'

Looking up this issue via Google, there wasn't really a lot of information on this particular build failure. Most suggestions were to change the location of the Derived Data folder (Xcode -> File -> Project Settings -> update location of derived data from default to relative)

This was one of the only actionable solutions I found online but this doesn't fully address the issue for me, it just creates a new issue: "Command PhaseScriptExecution failed with a nonzero exit code"

I feel like with enough digging around I should be able to find a solution to the "PhaseScriptExecution" issue; there seems to be a decent amount of information online about that particular problem. I would prefer if I could solve the original 'SwiftGeneratePch" failure without needing to address other issues, though. Is this possible?

Issues updating to Xcode 26 -- can no longer successfully build project
 
 
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