[PATCH] D153889: [analyzer][NFC] Fix dangling StringRef in barely used code

[Donát Nagy via Phabricator via cfe-commits]

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`CheckerContext::getNoteTag` has a shorthand version that takes a plain '`StringRef Note`' instead of a lambda that calculates the note.

The old implementation of this method was incorrect because it created a lambda that captured the StringRef, which was dereferenced much later, when the NoteTags were visited.

In the current codebase this does not cause errors because this method is called only once, and there the `Note` argument is a string literal that remains valid. However, I tried to use this method in a checker that I was prototyping, and there it printed random memory junk (instead of the message that I composed in a local variable).


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D153889

Files:
  clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h


Index: clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
===================================================================
--- clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
+++ clang/include/clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h
@@ -316,8 +316,8 @@
   ///        bug path significantly shorter.
   const NoteTag *getNoteTag(StringRef Note, bool IsPrunable = false) {
     return getNoteTag(
-        [Note](BugReporterContext &,
-               PathSensitiveBugReport &) { return std::string(Note); },
+        [Note = std::string(Note)](BugReporterContext &,
+               PathSensitiveBugReport &) { return Note; },
         IsPrunable);
   }
 


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