[clang] [Clang] Check consteval calls in lambda init-captures (PR #229953)

[Mariya Podchishchaeva via cfe-commits]

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@@ -5770,10 +5770,15 @@ struct ImmediateCallVisitor : DynamicRecursiveASTVisitor {
   // A nested lambda might have parameters with immediate invocations
   // in their default arguments.
   // The compound statement is not visited (as it does not constitute a
-  // subexpression).
-  // FIXME: We should consider visiting and transforming captures
-  // with init expressions.
+  // subexpression). Init-capture expressions, however, are evaluated as part
+  // of the lambda expression and need to be checked here.
   bool VisitLambdaExpr(LambdaExpr *E) override {
+    auto Init = E->capture_init_begin();
+    for (const LambdaCapture &Capture : E->captures()) {
+      if (E->isInitCapture(&Capture) && !TraverseStmt(*Init))
+        return false;
+      ++Init;
----------------
Fznamznon wrote:

Will it break if lambda has both regular and init-captures mixed? Maybe something like
```
struct S {
  int member = [this, captured = W(gv).value] { return captured; }();
};
```



https://github.com/llvm/llvm-project/pull/229953