diff --git a/cpp/cmake_modules/BuildUtils.cmake b/cpp/cmake_modules/BuildUtils.cmake
index 1234567..abcdefg 100644
--- a/cpp/cmake_modules/BuildUtils.cmake
+++ b/cpp/cmake_modules/BuildUtils.cmake
@@ -110,7 +110,7 @@
     execute_process(COMMAND ${LIBTOOL_MACOS} -V
                     OUTPUT_VARIABLE LIBTOOL_V_OUTPUT
                     OUTPUT_STRIP_TRAILING_WHITESPACE)
-    if(NOT "${LIBTOOL_V_OUTPUT}" MATCHES ".*cctools-([0-9.]+).*")
+    if(NOT "${LIBTOOL_V_OUTPUT}" MATCHES ".*cctools[-_a-z]*([0-9.]+).*")
       message(FATAL_ERROR "libtool found appears not to be Apple's libtool: ${LIBTOOL_MACOS}"
       )
     endif()
diff --git a/cpp/src/arrow/acero/source_node.cc b/cpp/src/arrow/acero/source_node.cc
index 0f5840676..cf68bfdcb 100644
--- a/cpp/src/arrow/acero/source_node.cc
+++ b/cpp/src/arrow/acero/source_node.cc
@@ -407,7 +407,7 @@ struct SchemaSourceNode : public SourceNode {
 struct RecordBatchReaderSourceNode : public SourceNode {
   RecordBatchReaderSourceNode(ExecPlan* plan, std::shared_ptr<Schema> schema,
                               arrow::AsyncGenerator<std::optional<ExecBatch>> generator)
-      : SourceNode(plan, schema, generator) {}
+      : SourceNode(plan, schema, generator, Ordering::Implicit()) {}
 
   static Result<ExecNode*> Make(ExecPlan* plan, std::vector<ExecNode*> inputs,
                                 const ExecNodeOptions& options) {