[clang] [clang][Sema] Fix initialization of `NonTypeTemplateParmDecl`... (PR #121768)

[Younan Zhang via cfe-commits]

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In-Reply-To: <llvm.org/llvm/llvm-project/pull/121768 at github.com>


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@@ -1983,15 +1983,17 @@ void ASTDeclWriter::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
   // For an expanded parameter pack, record the number of expansion types here
   // so that it's easier for deserialization to allocate the right amount of
   // memory.
-  Expr *TypeConstraint = D->getPlaceholderTypeConstraint();
-  Record.push_back(!!TypeConstraint);
+  Record.push_back(D->hasPlaceholderTypeConstraint());
   if (D->isExpandedParameterPack())
     Record.push_back(D->getNumExpansionTypes());
 
   VisitDeclaratorDecl(D);
   // TemplateParmPosition.
   Record.push_back(D->getDepth());
   Record.push_back(D->getPosition());
+  Expr *TypeConstraint = D->getPlaceholderTypeConstraint();
+  Record.push_back(/*PlaceholderTypeConstraintInitialized=*/TypeConstraint !=
+                   nullptr);
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zyn0217 wrote:

Can we only serialize `PlaceholderTypeConstraintInitialized` only when `D->hasPlaceholderTypeConstraint()` so that we can save up a bit for a number of cases?

https://github.com/llvm/llvm-project/pull/121768