[BoundsSafety][NFC] Remove the unused parameter 'Decls' from 'Sema::C… (#102076)

…heckCountedByAttrOnField'

llvm::SmallVectorImpl<TypeCoupledDeclRefInfo> &Decls is a vector of
declarations referred to by the argument of 'counted_by' attributes and
fields. 'BuildCountAttributedArrayOrPointerType' had been made
self-contained to produce the 'Decls' within itself to allow
'TreeTransform' to invoke the function without having to call
'Sema::CheckCountedByAttrOnField' again. Thus, 'Decls' produced by
`Sema::CheckCountedByAttrOnField` is never used.

Author: rapidsna

clang/include/clang/Sema/Sema.h

@@ -15071,9 +15071,6 @@ class Sema final : public SemaBase {
   ///
   /// \param FD The FieldDecl to apply the attribute to
   /// \param E The count expression on the attribute
-  /// \param[out] Decls If the attribute is semantically valid \p Decls
-  ///             is populated with TypeCoupledDeclRefInfo objects, each
-  ///             describing Decls referred to in \p E.
   /// \param CountInBytes If true the attribute is from the "sized_by" family of
   ///                     attributes. If the false the attribute is from
   ///                     "counted_by" family of attributes.
@@ -15086,10 +15083,8 @@ class Sema final : public SemaBase {
   /// `counted_by_or_null` attribute.
   ///
   /// \returns false iff semantically valid.
-  bool CheckCountedByAttrOnField(
-      FieldDecl *FD, Expr *E,
-      llvm::SmallVectorImpl<TypeCoupledDeclRefInfo> &Decls, bool CountInBytes,
-      bool OrNull);
+  bool CheckCountedByAttrOnField(FieldDecl *FD, Expr *E, bool CountInBytes,
+                                 bool OrNull);
 
   ///@}
 };

clang/lib/Sema/SemaBoundsSafety.cpp

@@ -48,10 +48,8 @@ enum class CountedByInvalidPointeeTypeKind {
   VALID,
 };
 
-bool Sema::CheckCountedByAttrOnField(
-    FieldDecl *FD, Expr *E,
-    llvm::SmallVectorImpl<TypeCoupledDeclRefInfo> &Decls, bool CountInBytes,
-    bool OrNull) {
+bool Sema::CheckCountedByAttrOnField(FieldDecl *FD, Expr *E, bool CountInBytes,
+                                     bool OrNull) {
   // Check the context the attribute is used in
 
   unsigned Kind = getCountAttrKind(CountInBytes, OrNull);
@@ -185,8 +183,6 @@ bool Sema::CheckCountedByAttrOnField(
       return true;
     }
   }
-
-  Decls.push_back(TypeCoupledDeclRefInfo(CountFD, /*IsDref*/ false));
   return false;
 }
 

clang/lib/Sema/SemaDeclAttr.cpp

@@ -5898,8 +5898,7 @@ static void handleCountedByAttrField(Sema &S, Decl *D, const ParsedAttr &AL) {
     llvm_unreachable("unexpected counted_by family attribute");
   }
 
-  llvm::SmallVector<TypeCoupledDeclRefInfo, 1> Decls;
-  if (S.CheckCountedByAttrOnField(FD, CountExpr, Decls, CountInBytes, OrNull))
+  if (S.CheckCountedByAttrOnField(FD, CountExpr, CountInBytes, OrNull))
     return;
 
   QualType CAT = S.BuildCountAttributedArrayOrPointerType(