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

[Malavika Samak via cfe-commits]

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@@ -2261,6 +2262,12 @@ class UnsafeBufferUsageReporter : public UnsafeBufferUsageHandler {
         // note_unsafe_buffer_operation doesn't have this mode yet.
         assert(!IsRelatedToDecl && "Not implemented yet!");
         MsgParam = 3;
+      } else if (isa<MemberExpr>(Operation)) {
+        // note_unsafe_buffer_operation doesn't have this mode yet.
+        assert(!IsRelatedToDecl && "Not implemented yet!");
+        auto ME = dyn_cast<MemberExpr>(Operation);
+        name = ME->getMemberDecl()->getName();
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malavikasamak wrote:

Sounds good, I will use the Decl and also add a test. I wasn't aware that it is unusual to put a field name in there. 

Side note: we should probably also provide the Decl, when the attribute is added to method overloads. Perhaps that needs to be a separate PR?

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