[clang] [Clang][Sema] Add -Wstringop-overread warning for source buffer overreads (PR #183004)

[Erich Keane via cfe-commits]

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@@ -1179,25 +1167,24 @@ void Sema::checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD,
     if (NewIndex >= TheCall->getNumArgs())
       return std::nullopt;
     return NewIndex;
-  };
+  }
 
-  auto ComputeExplicitObjectSizeArgument =
-      [&](unsigned Index) -> std::optional<llvm::APSInt> {
+  std::optional<llvm::APSInt>
+  ComputeExplicitObjectSizeArgument(unsigned Index) {
     std::optional<unsigned> IndexOptional = TranslateIndex(Index);
     if (!IndexOptional)
       return std::nullopt;
     unsigned NewIndex = *IndexOptional;
     Expr::EvalResult Result;
     Expr *SizeArg = TheCall->getArg(NewIndex);
-    if (!SizeArg->EvaluateAsInt(Result, getASTContext()))
+    if (!SizeArg->EvaluateAsInt(Result, S.getASTContext()))
       return std::nullopt;
     llvm::APSInt Integer = Result.Val.getInt();
     Integer.setIsUnsigned(true);
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erichkeane wrote:

What is going on here?  Why are we changing the sign?

https://github.com/llvm/llvm-project/pull/183004