[PATCH] D130550: [pseudo] Start rules are `_ := start-symbol EOF`, improve recovery.

[Haojian Wu via Phabricator via cfe-commits]

hokein added a comment.

+1 on this change, it would make the expose-lookahead-index-to-guard change easier.



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Comment at: clang-tools-extra/pseudo/include/clang-pseudo/GLR.h:74
     bool GCParity;
+    // Have we already used this node for error recovery? (prevents loops)
+    mutable bool Recovered = false;
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haven't look at it deeply -- is this bug related to this eof change? This looks like a different bug in recovery.


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Comment at: clang-tools-extra/pseudo/lib/Forest.cpp:191
+  // This is important to drive the final shift/recover/reduce loop.
+  new (&Terminals[Index])
+      ForestNode(ForestNode::Terminal, tokenSymbol(tok::eof),
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nit: in the underlying TokenStream implementation, `tokens()` has a trailing eof token, I think we can fold this into the above loop (if we expose a `token_eof()` method in TokenStream). Not sure we should do this. 


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D130550/new/

https://reviews.llvm.org/D130550