diff --git a/cpp/src/arrow/python/common.cc b/cpp/src/arrow/python/common.cc
index b954c1fc17f79..c83b2302ab59a 100644
--- a/cpp/src/arrow/python/common.cc
+++ b/cpp/src/arrow/python/common.cc
@@ -160,7 +160,8 @@ bool IsPythonError(const Status& status) {
     return false;
   }
   auto detail = status.detail();
-  return detail != nullptr && detail->type_id() == kErrorDetailTypeId;
+  bool result = detail != nullptr && detail->type_id() == kErrorDetailTypeId;
+  return result;
 }
 
 }  // namespace py
diff --git a/cpp/src/arrow/status.cc b/cpp/src/arrow/status.cc
index 5ca79d68959fd..5a81a60cdc42e 100644
--- a/cpp/src/arrow/status.cc
+++ b/cpp/src/arrow/status.cc
@@ -31,7 +31,6 @@ Status::Status(StatusCode code, std::string msg, std::shared_ptr<StatusDetail> d
   state_->code = code;
   state_->msg = std::move(msg);
   if (detail != nullptr) {
-    std::cerr << "!!!!!!non null detail" << detail;
     state_->detail = std::move(detail);
   }
 }
@@ -42,7 +41,6 @@ void Status::CopyFrom(const Status& s) {
     state_ = nullptr;
   } else {
     state_ = new State(*s.state_);
-    std::cerr << "!!!!copy_from " << state_->detail;
   }
 }
 
diff --git a/cpp/src/plasma/common.cc b/cpp/src/plasma/common.cc
index 84a1601952e80..00391af2192fb 100644
--- a/cpp/src/plasma/common.cc
+++ b/cpp/src/plasma/common.cc
@@ -51,6 +51,9 @@ class PlasmaStatusDetail : public arrow::StatusDetail {
       case PlasmaErrorCode::PlasmaObjectAlreadySealed:
         type = "Plasma object is already sealed";
         break;
+      default:
+        type = "Unknown plasma error";
+        break;
     }
     return std::string(type);
   }
diff --git a/python/pyarrow/includes/libarrow.pxd b/python/pyarrow/includes/libarrow.pxd
index f3ec032a33aad..e39657405c4dc 100644
--- a/python/pyarrow/includes/libarrow.pxd
+++ b/python/pyarrow/includes/libarrow.pxd
@@ -1207,7 +1207,7 @@ cdef extern from "arrow/python/api.h" namespace "arrow::py" nogil:
     shared_ptr[CDataType] GetPrimitiveType(Type type)
     shared_ptr[CDataType] GetTimestampType(TimeUnit unit)
 
-    cdef c_bool IsPythonError(const CStatus& status)
+    c_bool IsPythonError(const CStatus& status)
     object PyHalf_FromHalf(npy_half value)
 
     cdef cppclass PyConversionOptions: