[clang] Add Clang attribute to ensure that fields are initialized explicitly (PR #102040)

[Erich Keane via cfe-commits]

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@@ -2837,6 +2837,10 @@ bool QualType::hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD) {
   return RD->hasNonTrivialToPrimitiveCopyCUnion();
 }
 
+bool QualType::hasUninitializedExplicitInitFields(const RecordDecl *RD) {
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erichkeane wrote:

This is a bit of a weird one, why is this in `QualTYpe` but takes the thing anyway?  Should the implementation here be `getAsRecordDecl()->hasUnin...` ?

https://github.com/llvm/llvm-project/pull/102040