[clang] [NFC][CLANG] Fix null pointer dereferences (PR #86760)

[via cfe-commits]

https://github.com/smanna12 created https://github.com/llvm/llvm-project/pull/86760

This patch replaces getAs<> with castAs<> to resolve potential static analyzer bugs for

1. Dereferencing Proto1->param_type_begin(), which is known to be nullptr
2. Dereferencing Proto2->param_type_begin(), which is known to be nullptr
3. Dereferencing a pointer issue with nullptr Proto1 when calling param_type_end()
4. Dereferencing a pointer issue with nullptr Proto2 when calling param_type_end()

in clang::Sema::getMoreSpecializedTemplate().

>From f911587a8b5b9f25b9d35e7edd95cf98bf0cde3d Mon Sep 17 00:00:00 2001
From: "Manna, Soumi" <soumi.manna at intel.com>
Date: Tue, 26 Mar 2024 19:47:50 -0700
Subject: [PATCH] [NFC][CLANG] Fix null pointer dereferences

This patch replaces getAs<> with castAs<> to resolve potential static
analyzer bugs for

1. Dereferencing Proto1->param_type_begin(), which is known to be nullptr
2. Dereferencing Proto2->param_type_begin(), which is known to be nullptr
3. Dereferencing a pointer issue with nullptr Proto1 when calling param_type_end()
4. Dereferencing a pointer issue with nullptr Proto2 when calling param_type_end()

in clang::Sema::getMoreSpecializedTemplate().
---
 clang/lib/Sema/SemaTemplateDeduction.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Sema/SemaTemplateDeduction.cpp b/clang/lib/Sema/SemaTemplateDeduction.cpp
index 97f8445bf819c8..9a55881f644254 100644
--- a/clang/lib/Sema/SemaTemplateDeduction.cpp
+++ b/clang/lib/Sema/SemaTemplateDeduction.cpp
@@ -5514,9 +5514,9 @@ FunctionTemplateDecl *Sema::getMoreSpecializedTemplate(
   QualType Obj2Ty;
   if (TPOC == TPOC_Call) {
     const FunctionProtoType *Proto1 =
-        FD1->getType()->getAs<FunctionProtoType>();
+        FD1->getType()->castAs<FunctionProtoType>();
     const FunctionProtoType *Proto2 =
-        FD2->getType()->getAs<FunctionProtoType>();
+        FD2->getType()->castAs<FunctionProtoType>();
 
     //   - In the context of a function call, the function parameter types are
     //     used.