[NFC][CLANG] Fix issue with dereference null return value found by Coverity static analyzer tool
Reported by Coverity static analyzer tool:
Inside "ItaniumCXXABI.cpp" file, in <unnamed>::ItaniumCXXABI::EmitLoadOfMemberFunctionPointer(clang::CodeGen::CodeGenFunction &, clang::Expr const *, clang::CodeGen::Address, llvm::Value *&, llvm::Value *, clang::MemberPointerType const *): Return value of function which returns null is dereferenced without checking.
//returned_null: getAs returns nullptr (checked 130 out of 156 times).
//var_assigned: Assigning: FPT = nullptr return value from getAs.
const FunctionProtoType *FPT =
MPT->getPointeeType()->getAs<FunctionProtoType>();
auto *RD =
cast<CXXRecordDecl>(MPT->getClass()->castAs<RecordType>()->getDecl());
// Dereference null return value (NULL_RETURNS)
//dereference: Dereferencing a pointer that might be nullptr FPT when calling arrangeCXXMethodType.
llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(
CGM.getTypes().arrangeCXXMethodType(RD, FPT, /*FD=*/nullptr));
This patch uses castAs instead of getAs which will assert if the type doesn't match.
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D151054