[clang] Implement resource binding type prefix mismatch diagnostic infrastructure (PR #97103)

[Damyan Pepper via cfe-commits]

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@@ -551,24 +541,21 @@ getHLSLResourceAttrFromEitherDecl(VarDecl *VD,
 
     // the resource attr could be on the record decl itself or on one of
     // its fields (the resource handle, most commonly)
-    const auto *Attr = TheRecordDecl->getAttr<HLSLResourceAttr>();
+    const auto *Attr = TheRecordDecl->getAttr<T>();
     if (!Attr) {
       for (auto *FD : TheRecordDecl->fields()) {
-        Attr = FD->getAttr<HLSLResourceAttr>();
+        Attr = FD->getAttr<T>();
         if (Attr)
           break;
       }
     }
     return Attr;
-  } else if (CBufferOrTBuffer) {
-    const auto *Attr = CBufferOrTBuffer->getAttr<HLSLResourceAttr>();
-    return Attr;
   }
-  llvm_unreachable("one of the two conditions should be true.");
+  llvm_unreachable("VD should not be null");
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damyanp wrote:

How about removing the `if` and either have an `assert(VD);` at the beginning of the function.  But really, I don't think you'd bother doing that if you wrote this function from scratch to just take the one parameter, it's just because this is left over from the previous version that had two arguments that these null checks were left behind.

https://github.com/llvm/llvm-project/pull/97103