[PATCH] D72860: [modules] Do not cache invalid state for modules that we attempted to load.

[Richard Smith - zygoloid via Phabricator via cfe-commits]

rsmith added inline comments.


================
Comment at: clang/lib/Serialization/ModuleManager.cpp:183
       // Get a buffer of the file and close the file descriptor when done.
-      Buf = FileMgr.getBufferForFile(NewModule->File, /*isVolatile=*/false);
+      Buf = FileMgr.getBufferForFile(NewModule->File, /*isVolatile=*/true);
     }
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dexonsmith wrote:
> vsapsai wrote:
> > Made this change because if we don't have a valid module but opened a corresponding .pcm file earlier, there is a high chance that .pcm file was rebuilt.
> Please add a comment in the code explaining that.
This change is proving really bad for us. This prevents using `mmap` for loading module files, and instead forces the entire file to be loaded every time. Please revert.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D72860/new/

https://reviews.llvm.org/D72860