[clang] [clang][CodeGen] Check initializer of zero-size fields for nullptr (PR #109271)

[Eli Friedman via cfe-commits]

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@@ -738,7 +738,7 @@ bool ConstStructBuilder::Build(const InitListExpr *ILE, bool AllowOverwrite) {
     // Zero-sized fields are not emitted, but their initializers may still
     // prevent emission of this struct as a constant.
     if (isEmptyFieldForLayout(CGM.getContext(), Field)) {
-      if (Init->HasSideEffects(CGM.getContext()))
+      if (Init && Init->HasSideEffects(CGM.getContext()))
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efriedma-quic wrote:

Maybe we should look at making InitListExpr handling more consistent, though... it looks like we generate an implicit initializer expression for C++ classes, but not other cases.  But this should do the right thing.

https://github.com/llvm/llvm-project/pull/109271