[clang] [clang-tools-extra] [llvm] [clang] WIP: Improved Context Declaration tracking (PR #107942)

[Younan Zhang via cfe-commits]

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@@ -7946,6 +7980,8 @@ class Sema final : public SemaBase {
   /// A stack of expression evaluation contexts.
   SmallVector<ExpressionEvaluationContextRecord, 8> ExprEvalContexts;
 
+  SmallVector<Decl *, 8> PendingLazyContextDecls;
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zyn0217 wrote:

So from a quick reading, PendingLazyContextDecls is used for lambdas created as part of other declarations, such as being part of a default argument for a template parameter. Their context declarations are updated only at the end of the evaluation context or right after the outer declaration is created.

I think we'd better document its intent, wdyt?

https://github.com/llvm/llvm-project/pull/107942