[clang] [Clang][NFC] Fix potential null dereference in encodeTypeForFunctionPointerAuth (PR #104737)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: None (smanna12)

<details>
<summary>Changes</summary>

This patch replaces getAs with castAs to prevent dereferencing a potential null pointer, ensuring type safety as per static analysis report.

---
Full diff: https://github.com/llvm/llvm-project/pull/104737.diff


1 Files Affected:

- (modified) clang/lib/AST/ASTContext.cpp (+1-1) 


``````````diff
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index f35a025fc8edfc..b201d201e1ea6a 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -3279,7 +3279,7 @@ static void encodeTypeForFunctionPointerAuth(const ASTContext &Ctx,
 
   case Type::MemberPointer: {
     OS << "M";
-    const auto *MPT = T->getAs<MemberPointerType>();
+    const auto *MPT = T->castAs<MemberPointerType>();
     encodeTypeForFunctionPointerAuth(Ctx, OS, QualType(MPT->getClass(), 0));
     encodeTypeForFunctionPointerAuth(Ctx, OS, MPT->getPointeeType());
     return;

``````````

</details>


https://github.com/llvm/llvm-project/pull/104737