[clang] [BoundsSafety][Clang][Sema][AST] Introduce CThisExpr for C __counted_by attributes (PR #199241)

[Karthik P via cfe-commits]

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@@ -335,6 +335,16 @@ ExprDependence clang::computeDependence(CXXThisExpr *E) {
   return D;
 }
 
+ExprDependence clang::computeDependence(CThisExpr *E) {
+  // The implicit reference is type-dependent if the enclosing record type
+  // is dependent. This primarily matters when the C struct is utilized 
+  // within a C++ template context. 
+  // Unlike CXXThisExpr, CThisExpr cannot be captured by lambdas or 
+  // explicitly object parameters, so we only need to forward the implied 
+  // type's dependence.
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Caryoake wrote:

Got it yep

https://github.com/llvm/llvm-project/pull/199241