Is this gyp or gn? Either way, the exact settings would be useful to make sure we fix the right problem. So, please share the GYP_DEFINES or args.gn.

Previously this type of error would be impossible because we didn't use incremental linking on release builds (IIRC). I know that there was discussion about using incremental linking on all component builds - did that happen? If so then I suspect that the fix is to forcibly disable incremental linking on large targets - this probably includes all of the large test binaries.

Hmm, weird, it linked today after I synced...

FTR this was with GN:
   is_component_build = true
   is_debug = false
   is_chrome_branded = true
   dcheck_always_on = true
   is_win_fastlink = true
   enable_nacl = false

I'll close for now. It might mean that we're getting close to some threshold and I went back under it after rebuilding all?

There has been some churn in this area. Specifically crrev.com/2060983002, crrev.com/2043873004, crrev.com/2063483002, etc.

The basic problem is that source sets tend to lead to unnecessarily long link times on targets that need very few of the .obj file, but .lib files tend to hit file size limits. I suspect that these ILK size limits are being affected by the changes back and forth between source sets and libs.