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

[via cfe-commits]

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@@ -6014,6 +6014,10 @@ static void handleNoMergeAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   D->addAttr(NoMergeAttr::Create(S.Context, AL));
 }
 
+static void handleExplicitInitAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
+  D->addAttr(ExplicitInitAttr::Create(S.Context, AL));
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higher-performance wrote:

I have added diagnosis to handle this elsewhere, please see update.

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