[clang] [Clang][Interp] Fix handling of `DecompositionDecl` (PR #100400)

[via cfe-commits]

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@@ -3593,8 +3593,14 @@ VarCreationState Compiler<Emitter>::visitDecl(const VarDecl *VD) {
   if (R.notCreated())
     return R;
 
-  if (R)
-    return true;
+  if (R) {
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yronglin wrote:

This change just follow current ExprConstant's behavior, but it's no value for this issue, should we remove it?

https://github.com/llvm/llvm-project/pull/100400