[PATCH] D125311: [pseudo] Share the underly payload when stripping comments for a token stream

[Haojian Wu via Phabricator via cfe-commits]

hokein created this revision.
hokein added a reviewer: sammccall.
Herald added a project: All.
hokein requested review of this revision.
Herald added a subscriber: alextsao1999.
Herald added a project: clang-tools-extra.

`stripComments(cook(...))` is a common pattern being written.
Without this patch, this has a use-after-free issue (cook returns a temporary
TokenStream object which has its own payload, but the payload is not
shared with the one returned by stripComments).


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D125311

Files:
  clang-tools-extra/pseudo/include/clang-pseudo/Token.h
  clang-tools-extra/pseudo/lib/Token.cpp


Index: clang-tools-extra/pseudo/lib/Token.cpp
===================================================================
--- clang-tools-extra/pseudo/lib/Token.cpp
+++ clang-tools-extra/pseudo/lib/Token.cpp
@@ -116,7 +116,7 @@
 }
 
 TokenStream stripComments(const TokenStream &Input) {
-  TokenStream Out;
+  TokenStream Out(Input.getPayload());
   for (const Token &T : Input.tokens()) {
     if (T.Kind == tok::comment)
       continue;
Index: clang-tools-extra/pseudo/include/clang-pseudo/Token.h
===================================================================
--- clang-tools-extra/pseudo/include/clang-pseudo/Token.h
+++ clang-tools-extra/pseudo/include/clang-pseudo/Token.h
@@ -161,6 +161,9 @@
     return Storage[1];
   }
 
+  /// Returns the shared payload.
+  std::shared_ptr<void> getPayload() const { return Payload; }
+
   /// Print the tokens in this stream to the output stream.
   ///
   /// The presence of newlines/spaces is preserved, but not the quantity.


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