[PATCH] D53866: [Preamble] Fix preamble for circular #includes

Tue Dec 4 00:53:37 PST 2018

ilya-biryukov added inline comments.

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Comment at: include/clang/Lex/Preprocessor.h:391
   } PreambleConditionalStack;
+  bool PreambleGenerationFailed = false;

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There's a mechanism to handle preamble with errors, see `PreprocessorOpts::AllowPCHWithCompilerErrors`.
Maybe rely on it and avoid adding a different one?

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Comment at: lib/Lex/PPDirectives.cpp:1945
+    // Generate a fatal error to skip further processing.
+    Diag(FilenameTok.getLocation(), diag::err_pp_error_opening_file) << ""
+                                                                     << "";
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Maybe add a new error or find a more appropriate existing one to reuse?
"Error opening file", especially without any arguments does not provide enough context to figure out what went wrong.

Repository:
  rC Clang

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D53866/new/

https://reviews.llvm.org/D53866