[clang] [Clang] Add template argument support for {con,de}structor attributes. (PR #151400)

[Erich Keane via cfe-commits]

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@@ -2152,29 +2152,49 @@ static void handleUnusedAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   D->addAttr(::new (S.Context) UnusedAttr(S.Context, AL));
 }
 
+static std::optional<Expr *>
+sharedGetConstructorDestructorAttrExpr(Sema &S, const ParsedAttr &AL) {
+  // If no Expr node exists on the attribute, return a nullptr (default priority to be used).
+  // If Expr node exists but is not valid, return a nullopt.
+  // Otherwise, return the Expr.
+  Expr *E = nullptr;
+  if (AL.getNumArgs() == 1) {
+    E = AL.getArgAsExpr(0);
+    if (E->isValueDependent()) {
+      if (!E->isTypeDependent() && !E->getType()->isIntegerType()) {
+        S.Diag(AL.getLoc(), diag::err_attribute_argument_type)
+            << AL << AANT_ArgumentIntegerConstant << E->getSourceRange();
+        return std::nullopt;
+      }
+    } else {
+      uint32_t priority;
+      if (!S.checkUInt32Argument(AL, AL.getArgAsExpr(0), priority)) {
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erichkeane wrote:

Yep!  exactly!  You have an additional couple of APInt/APValue/etc casts there (just do `llvm::APSInt::getUnsigned(priority)`), 

https://github.com/llvm/llvm-project/pull/151400