[clang] [clang-tools-extra] [llvm] [clang] Fix false positive -Wmissing-field-initializer for anonymous unions (PR #70829)

[Richard Smith via cfe-commits]

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@@ -465,7 +460,8 @@ class InitListChecker {
   void FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
                                const InitializedEntity &ParentEntity,
                                InitListExpr *ILE, bool &RequiresSecondPass,
-                               bool FillWithNoInit = false);
+                               bool FillWithNoInit = false,
+                               bool MaybeEmitMFIWarning = true);
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zygoloid wrote:

This is not an initialism that we can expect future readers of the code to understand. If you want to keep this short, how about something like `WarnIfMissing`?

https://github.com/llvm/llvm-project/pull/70829