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

[Ziqing Luo via cfe-commits]

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@@ -1670,30 +1936,41 @@ class ULCArraySubscriptGadget : public FixableGadget {
 };
 
 // Fixable gadget to handle stand alone pointers of the form `UPC(DRE)` in the
-// unspecified pointer context (isInUnspecifiedPointerContext). The gadget emits
-// fixit of the form `UPC(DRE.data())`.
+// unspecified pointer context (findStmtsInUnspecifiedPointerContext). The
+// gadget emits fixit of the form `UPC(DRE.data())`.
 class UPCStandalonePointerGadget : public FixableGadget {
 private:
   static constexpr const char *const DeclRefExprTag = "StandalonePointer";
   const DeclRefExpr *Node;
 
 public:
-  UPCStandalonePointerGadget(const MatchFinder::MatchResult &Result)
+  UPCStandalonePointerGadget(const MatchResult &Result)
       : FixableGadget(Kind::UPCStandalonePointer),
-        Node(Result.Nodes.getNodeAs<DeclRefExpr>(DeclRefExprTag)) {
+        Node(Result.getNodeAs<DeclRefExpr>(DeclRefExprTag)) {
     assert(Node != nullptr && "Expecting a non-null matching result");
   }
 
   static bool classof(const Gadget *G) {
     return G->getKind() == Kind::UPCStandalonePointer;
   }
 
-  static Matcher matcher() {
-    auto ArrayOrPtr = anyOf(hasPointerType(), hasArrayType());
-    auto target = expr(ignoringParenImpCasts(
-        declRefExpr(allOf(ArrayOrPtr, toSupportedVariable()))
-            .bind(DeclRefExprTag)));
-    return stmt(isInUnspecifiedPointerContext(target));
+  static bool matches(const Stmt *S,
+                      llvm::SmallVectorImpl<MatchResult> &Results) {
+    bool Found = false;
+    findStmtsInUnspecifiedPointerContext(S, [&Found, &Results](const Stmt *S) {
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ziqingluo-90 wrote:

nit: for these functions like `findStmtsInUnspecifiedPointerContext`, can we change the type of the second parameter to `llvm::function_ref<bool(const Stmt *)>`?  I just feel like it would be a bit more intuitive than capturing `Found`.

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