[clang] [attributes][-Wunsafe-buffer-usage] Support adding unsafe_buffer_usage attribute to struct fields (PR #101585)

[via cfe-commits]

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@@ -927,21 +927,28 @@ class CArrayToPtrAssignmentGadget : public FixableGadget {
 /// over one of its pointer parameters.
 class UnsafeBufferUsageAttrGadget : public WarningGadget {
   constexpr static const char *const OpTag = "call_expr";
-  const CallExpr *Op;
+  const Expr *Op;
 
 public:
   UnsafeBufferUsageAttrGadget(const MatchFinder::MatchResult &Result)
       : WarningGadget(Kind::UnsafeBufferUsageAttr),
-        Op(Result.Nodes.getNodeAs<CallExpr>(OpTag)) {}
+        Op(Result.Nodes.getNodeAs<Expr>(OpTag)) {}
 
   static bool classof(const Gadget *G) {
     return G->getKind() == Kind::UnsafeBufferUsageAttr;
   }
 
   static Matcher matcher() {
+    auto HasUnsafeFielDecl = 
+        member(fieldDecl(allOf(
+               anyOf(hasPointerType(), hasArrayType()),
+               hasAttr(attr::UnsafeBufferUsage))));
+ 
     auto HasUnsafeFnDecl =
         callee(functionDecl(hasAttr(attr::UnsafeBufferUsage)));
-    return stmt(callExpr(HasUnsafeFnDecl).bind(OpTag));
+
+    return stmt(expr(anyOf(callExpr(HasUnsafeFnDecl).bind(OpTag), 
+            memberExpr(HasUnsafeFielDecl).bind(OpTag))));
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jkorous-apple wrote:

I wonder if there's some other common way how to "use" fields in some sense but can't think of any.
Does this work for class templates?

https://github.com/llvm/llvm-project/pull/101585