[PATCH] Modules: Make missing headers in a module.map a warning not an error.

[Richard Smith]

  Please add a test that tries to import a module that contains a missing file. I expect that'll assert in `Module::isAvailable`, because it can't explain why the module is unavailable.


================
Comment at: lib/Lex/ModuleMap.cpp:1569
@@ +1568,3 @@
+    // If we find a module that has a missing header, we mark this module as
+    // unavailable. Layering warnings like -fmodules-decluse can still be used.
+    ActiveModule->IsAvailable = false;
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Presumably other submodules of the same module can still be built and used, too? (I don't think there's anything specific to layering warnings here?)


http://llvm-reviews.chandlerc.com/D2352