[clang] [Clang] Optimize -Wunsafe-buffer-usage. (PR #125492)

[Ilya Biryukov via cfe-commits]

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@@ -1711,25 +2008,38 @@ class PointerDereferenceGadget : public FixableGadget {
   const UnaryOperator *Op = nullptr;
 
 public:
-  PointerDereferenceGadget(const MatchFinder::MatchResult &Result)
+  PointerDereferenceGadget(const MatchResult &Result)
       : FixableGadget(Kind::PointerDereference),
-        BaseDeclRefExpr(
-            Result.Nodes.getNodeAs<DeclRefExpr>(BaseDeclRefExprTag)),
-        Op(Result.Nodes.getNodeAs<UnaryOperator>(OperatorTag)) {}
+        BaseDeclRefExpr(Result.getNodeAs<DeclRefExpr>(BaseDeclRefExprTag)),
+        Op(Result.getNodeAs<UnaryOperator>(OperatorTag)) {}
 
   static bool classof(const Gadget *G) {
     return G->getKind() == Kind::PointerDereference;
   }
 
-  static Matcher matcher() {
-    auto Target =
-        unaryOperator(
-            hasOperatorName("*"),
-            has(expr(ignoringParenImpCasts(
-                declRefExpr(toSupportedVariable()).bind(BaseDeclRefExprTag)))))
-            .bind(OperatorTag);
-
-    return expr(isInUnspecifiedLvalueContext(Target));
+  static bool matches(const Stmt *S, llvm::SmallVector<MatchResult> &Results) {
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ilya-biryukov wrote:

NIT: it's better to accept `llvm::SmallVectorImpl`, it allows to pass small vectors of arbitrary sizes from the outside.

(it's a common pattern in LLVM that's useful to be aware of)

https://github.com/llvm/llvm-project/pull/125492