[PATCH] D58497: Clear the KnownModules cache if the preprocessor is going away

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

rsmith added a comment.

Do we need `KnownModules` at all? It seems to serve a very similar purpose to the `Modules` string map on `ModuleMap`. (The main difference seems to be that `KnownModules` can cache module load failures.) If we can keep only a single data structure tracking this, owned by the `ModuleMap` (which also owns the modules), that should remove the possibility for dangling module pointers.


Repository:
  rC Clang

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D58497/new/

https://reviews.llvm.org/D58497