Index: source/Plugins/SymbolFile/PDB/PDBASTParser.cpp
===================================================================
--- source/Plugins/SymbolFile/PDB/PDBASTParser.cpp
+++ source/Plugins/SymbolFile/PDB/PDBASTParser.cpp
@@ -141,7 +141,7 @@
   } else if (auto func_sig = llvm::dyn_cast<PDBSymbolTypeFunctionSig>(&type)) {
     auto arg_enum = func_sig->getArguments();
     uint32_t num_args = arg_enum->getChildCount();
-    std::vector<CompilerType> arg_list(num_args);
+    std::vector<CompilerType> arg_list;
     while (auto arg = arg_enum->getNext()) {
       lldb_private::Type *arg_type =
           m_ast.GetSymbolFile()->ResolveTypeUID(arg->getSymIndexId());
@@ -152,6 +152,8 @@
       CompilerType arg_ast_type = arg_type->GetFullCompilerType();
       arg_list.push_back(arg_ast_type);
     }
+    lldbassert(arg_list.size() <= num_args);
+
     auto pdb_return_type = func_sig->getReturnType();
     lldb_private::Type *return_type =
         m_ast.GetSymbolFile()->ResolveTypeUID(pdb_return_type->getSymIndexId());
@@ -166,7 +168,7 @@
     if (func_sig->isVolatileType())
       type_quals |= clang::Qualifiers::Volatile;
     CompilerType func_sig_ast_type = m_ast.CreateFunctionType(
-        return_ast_type, &arg_list[0], num_args, false, type_quals);
+        return_ast_type, arg_list.data(), arg_list.size(), false, type_quals);
 
     return std::make_shared<lldb_private::Type>(
         func_sig->getSymIndexId(), m_ast.GetSymbolFile(), ConstString(), 0,