From d26eca7073371906c7cf320ce2712075c35246f0 Mon Sep 17 00:00:00 2001
From: Wuwei Lin <vincentl13x@gmail.com>
Date: Tue, 22 May 2018 15:51:08 +0800
Subject: [PATCH] Unref input features in transformer::apply

---
 src/shogun/preprocessor/DensePreprocessor.cpp  | 1 +
 src/shogun/preprocessor/SparsePreprocessor.h   | 1 +
 src/shogun/preprocessor/StringPreprocessor.cpp | 1 +
 3 files changed, 3 insertions(+)

diff --git a/src/shogun/preprocessor/DensePreprocessor.cpp b/src/shogun/preprocessor/DensePreprocessor.cpp
index eb235eee4fe..a9ef1c43534 100644
--- a/src/shogun/preprocessor/DensePreprocessor.cpp
+++ b/src/shogun/preprocessor/DensePreprocessor.cpp
@@ -97,6 +97,7 @@ CFeatures* CDensePreprocessor<ST>::apply(CFeatures* features, bool inplace)
 		matrix = matrix.clone();
 	auto feat_matrix = apply_to_matrix(matrix);
 	auto preprocessed = new CDenseFeatures<ST>(feat_matrix);
+	SG_UNREF(features);
 	SG_REF(preprocessed);
 	return preprocessed;
 }
diff --git a/src/shogun/preprocessor/SparsePreprocessor.h b/src/shogun/preprocessor/SparsePreprocessor.h
index 04fd253bc47..1698a4ff6bd 100644
--- a/src/shogun/preprocessor/SparsePreprocessor.h
+++ b/src/shogun/preprocessor/SparsePreprocessor.h
@@ -93,6 +93,7 @@ CFeatures* CSparsePreprocessor<ST>::apply(CFeatures* features, bool inplace)
 	apply_to_sparse_matrix(feature_matrix);
 
 	auto processed = new CSparseFeatures<ST>(feature_matrix);
+	SG_UNREF(features);
 	SG_REF(processed);
 
 	return processed;
diff --git a/src/shogun/preprocessor/StringPreprocessor.cpp b/src/shogun/preprocessor/StringPreprocessor.cpp
index 081ae9b0e60..b770adb6dbd 100644
--- a/src/shogun/preprocessor/StringPreprocessor.cpp
+++ b/src/shogun/preprocessor/StringPreprocessor.cpp
@@ -106,6 +106,7 @@ namespace shogun
 
 		auto processed = new CStringFeatures<ST>(
 		    string_list, string_features->get_alphabet());
+		SG_UNREF(features);
 		SG_REF(processed);
 
 		return processed;