[clang] [Sema] Migrate away from PointerUnion::dyn_cast (NFC) (PR #125630)

[Kazu Hirata via cfe-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/125630

Note that PointerUnion::dyn_cast has been soft deprecated in
PointerUnion.h:

  // FIXME: Replace the uses of is(), get() and dyn_cast() with
  //        isa<T>, cast<T> and the llvm::dyn_cast<T>

Literal migration would result in dyn_cast_if_present (see the
definition of PointerUnion::dyn_cast), but this patch uses dyn_cast
because we expect *Found to be nonnull.  Note that if *Found were
null, cast<VarDecl>(TransformedDecl) would trigger an assertion error.


>From 39b5e3693ebe165c4ae2f24bd532bc66e282828b Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Mon, 3 Feb 2025 16:29:00 -0800
Subject: [PATCH] [Sema] Migrate away from PointerUnion::dyn_cast (NFC)

Note that PointerUnion::dyn_cast has been soft deprecated in
PointerUnion.h:

  // FIXME: Replace the uses of is(), get() and dyn_cast() with
  //        isa<T>, cast<T> and the llvm::dyn_cast<T>

Literal migration would result in dyn_cast_if_present (see the
definition of PointerUnion::dyn_cast), but this patch uses dyn_cast
because we expect *Found to be nonnull.  Note that if *Found were
null, cast<VarDecl>(TransformedDecl) would trigger an assertion error.
---
 clang/lib/Sema/SemaTemplateInstantiate.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index dc3bfa97eff399..44bca0d667f764 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -2438,7 +2438,7 @@ TemplateInstantiator::TransformFunctionParmPackRefExpr(DeclRefExpr *E,
   assert(Found && "no instantiation for parameter pack");
 
   Decl *TransformedDecl;
-  if (DeclArgumentPack *Pack = Found->dyn_cast<DeclArgumentPack *>()) {
+  if (DeclArgumentPack *Pack = dyn_cast<DeclArgumentPack *>(*Found)) {
     // If this is a reference to a function parameter pack which we can
     // substitute but can't yet expand, build a FunctionParmPackExpr for it.
     if (getSema().ArgumentPackSubstitutionIndex == -1) {