[PATCH] D40094: LTO: clarify why we need to gracefully handle sys::fs::rename failures

[Peter Collingbourne via Phabricator via llvm-commits]

pcc added inline comments.


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Comment at: llvm/lib/LTO/Caching.cpp:77
+        // fail with a permission denied error (for example, if the destination
+        // is currently mmapped). Since the existing file should be semantically
+        // equivalent to the one we are trying to write, we give AddBuffer a
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The implementation already tries to handle this case by renaming the destination file. Probably the example that I'd choose is that the destination may have been opened by another process without sharing.


https://reviews.llvm.org/D40094