GaussianCheckerboard leaks

[vigsterkr]

check the latest output of memcheck: http://buildbot.shogun-toolbox.org/memcheck/20170623-0120.html

<b>MLK</b> ==13454== 8,810 (208 direct, 8,602 indirect) bytes in 1 blocks are definitely lost in loss record 589 of 592
==13454==    at 0x4C2C21F: operator new(unsigned long) (vg_replace_malloc.c:334)
==13454==    by 0x836F7CC: shogun::CDenseFeatures<double>::copy_subset(shogun::SGVector<int>) (DenseFeatures.cpp:622)
==13454==    by 0x1003495: GaussianCheckerboard::GaussianCheckerboard(int, int, int) (GaussianCheckerboard.h:93)
==13454==    by 0x10038FA: LinearTestEnvironment::LinearTestEnvironment() (LinearTestEnvironment.h:49)
==13454==    by 0x1002E42: main (main_unittest.cc:74)
==13454== 
<b>MLK</b> ==13454== 8,810 (208 direct, 8,602 indirect) bytes in 1 blocks are definitely lost in loss record 590 of 592
==13454==    at 0x4C2C21F: operator new(unsigned long) (vg_replace_malloc.c:334)
==13454==    by 0x836F7CC: shogun::CDenseFeatures<double>::copy_subset(shogun::SGVector<int>) (DenseFeatures.cpp:622)
==13454==    by 0x10034DD: GaussianCheckerboard::GaussianCheckerboard(int, int, int) (GaussianCheckerboard.h:95)
==13454==    by 0x10038FA: LinearTestEnvironment::LinearTestEnvironment() (LinearTestEnvironment.h:49)
==13454==    by 0x1002E42: main (main_unittest.cc:74)
==13454== 
<b>MLK</b> ==13454== 10,810 (208 direct, 10,602 indirect) bytes in 1 blocks are definitely lost in loss record 591 of 592
==13454==    at 0x4C2C21F: operator new(unsigned long) (vg_replace_malloc.c:334)
==13454==    by 0x836F7CC: shogun::CDenseFeatures<double>::copy_subset(shogun::SGVector<int>) (DenseFeatures.cpp:622)
==13454==    by 0x1003495: GaussianCheckerboard::GaussianCheckerboard(int, int, int) (GaussianCheckerboard.h:93)
==13454==    by 0x10039CE: MutiLabelTestEnvironment::MutiLabelTestEnvironment() (MutiLabelTestEnvironment.h:49)
==13454==    by 0x1002E5F: main (main_unittest.cc:75)
==13454== 
<b>MLK</b> ==13454== 10,810 (208 direct, 10,602 indirect) bytes in 1 blocks are definitely lost in loss record 592 of 592
==13454==    at 0x4C2C21F: operator new(unsigned long) (vg_replace_malloc.c:334)
==13454==    by 0x836F7CC: shogun::CDenseFeatures<double>::copy_subset(shogun::SGVector<int>) (DenseFeatures.cpp:622)
==13454==    by 0x10034DD: GaussianCheckerboard::GaussianCheckerboard(int, int, int) (GaussianCheckerboard.h:95)
==13454==    by 0x10039CE: MutiLabelTestEnvironment::MutiLabelTestEnvironment() (MutiLabelTestEnvironment.h:49)
==13454==    by 0x1002E5F: main (main_unittest.cc:75)

and this is in case of every unit test…. this is due to the fact that copy_subset if you check already calls SG_REF on the returned CFeatures, i.e. no need for the

SG_REF(features_train)
SG_REF(features_test)

in GaussianCheckerboard::GaussianCheckerboard

[vigsterkr]

@MikeLing @micmn