Inquiry: ThinLTO cache rename error & directory lock during CEF build on macOS

[张啸]

Hi Chromium Developers,

I am running into a consistent build failure on our Jenkins environment when compiling CEF 150.0.7871 using Xcode 26.2 on macOS 15.6.

Issue Description:

The build first fails during the solink step with the following LLVM cache error:

LLVM ERROR: Failed to rename temporary file thinlto-cache/Thin-eb6f9e.tmp.o to thinlto-cache/llvmcache-57F87D5F72E812F1585C9CCE98289C52EA343928: No such file or directory

Following this specific link failure, the build directory becomes completely locked. As a result, Jenkins is entirely unable to clean up or delete the workspace during the post-build phase. 

Even running rm -rf on the out directory doesn't work anymore.

Findings & Context

I found this behavior seems highly related to the public issue discussed here: https://issues.chromium.org/issues/491023043

However the comment in that thread points to https://issues.chromium.org/issues/40060675, which is unfortunately restricted and inaccessible to me.

.

Questions:

• Is this a known issue where ThinLTO/LLD on macOS leaks file handles or deadlocks during unexpected cache pruning/failures?
• Could someone with access kindly share the context or workaround discussed in the restricted  https://issues.chromium.org/issues/40060675?

Thank you for your time and help!