diff --git a/.github/workflows/githubci.yml b/.github/workflows/githubci.yml
index 44106cb..3b6599c 100644
--- a/.github/workflows/githubci.yml
+++ b/.github/workflows/githubci.yml
@@ -21,8 +21,7 @@ jobs:
       - name: Install Dependencies
         run: |
           if [[ $(uname) != "Darwin" ]]; then
-            sudo apt update
-            sudo apt install doxygen libcurl4-openssl-dev gcc-5 g++-5
+            sudo apt install doxygen libcurl4-openssl-dev gcc-4.8 g++-4.8
           else
             brew install libomp doxygen
           fi
@@ -33,7 +32,7 @@ jobs:
           TASK=lint ./scripts/test_script.sh
       - name: googletest
         run: |
-          if [[ "${{ matrix.task }}" == "s390x_test" ]]; then
-            docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+          if [[ $(uname) != "Darwin" ]]; then
+            docker run --rm --privileged multiarch/qemu-user-static:register --reset
           fi
           TASK=${{ matrix.task }} ./scripts/test_script.sh
diff --git a/CMakeLists.txt b/CMakeLists.txt
index a226ffa..141db72 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,7 +14,6 @@ include(cmake/Utils.cmake)
 
 # Options
 dmlccore_option(USE_HDFS "Build with HDFS support" OFF)
-dmlccore_option(DMLC_HDFS_SHARED "Build with dynamic HDFS library" OFF)
 dmlccore_option(USE_AZURE "Build with AZURE support" OFF)
 dmlccore_option(USE_S3 "Build with S3 support" OFF)
 dmlccore_option(USE_OPENMP "Build with OpenMP" ON)
@@ -72,11 +71,7 @@ if(USE_HDFS)
   find_package(HDFS REQUIRED)
   find_package(JNI REQUIRED)
   target_include_directories(dmlc PRIVATE ${HDFS_INCLUDE_DIR})
-  if (DMLC_HDFS_SHARED)
-    target_link_libraries(dmlc PRIVATE ${HDFS_LIBRARIES} ${JAVA_JVM_LIBRARY})
-  else()
-    target_link_libraries(dmlc PRIVATE ${HDFS_STATIC_LIB} ${JAVA_JVM_LIBRARY})
-  endif()
+  target_link_libraries(dmlc PRIVATE ${HDFS_STATIC_LIB} ${JAVA_JVM_LIBRARY})
   target_compile_definitions(dmlc PRIVATE -DDMLC_USE_HDFS=1)
 else()
   target_compile_definitions(dmlc PRIVATE -DDMLC_USE_HDFS=0)
diff --git a/Makefile b/Makefile
index d57c98f..2ecc78b 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,11 @@ NOLINT_FILES = --exclude_path include/dmlc/concurrentqueue.h include/dmlc/blocki
 # this is the common build script for dmlc lib
 export LDFLAGS= -pthread -lm
 export CFLAGS = -O3 -Wall -Wno-unknown-pragmas -Iinclude
-CFLAGS+=-std=c++11
+ifeq ($(USE_GNU11), 1)
+	CFLAGS += -std=gnu++11
+else
+	CFLAGS += -std=c++0x
+endif
 LDFLAGS+= $(DMLC_LDFLAGS) $(ADD_LDFLAGS)
 CFLAGS+= $(DMLC_CFLAGS) $(ADD_CFLAGS)
 
diff --git a/README.md b/README.md
index a81df98..e073d75 100644
--- a/README.md
+++ b/README.md
@@ -31,7 +31,7 @@ Contributing
 
 Contributing to dmlc-core is welcomed! dmlc-core follows google's C style guide. If you are interested in contributing, take a look at [feature wishlist](https://github.com/dmlc/dmlc-core/labels/feature%20wishlist) and open a new issue if you like to add something.
 
-* DMLC-Core uses C++11 standard. Ensure that your C++ compiler supports C++11.
+* Use of c++11 is allowed, given that the code is macro guarded with ```DMLC_USE_CXX11```
 * Try to introduce minimum dependency when possible
 
 ### CheckList before submit code
diff --git a/appveyor.yml b/appveyor.yml
index 19ffa64..54ba43f 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -22,6 +22,11 @@ environment:
         - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
           target: msys2
           generator: "Unix Makefiles"
+        - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+          target: msvc
+          ver: 2013
+          generator: "Visual Studio 12 2013 Win64"
+          configuration: Release
         - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
           target: msvc
           ver: 2015
diff --git a/doc/Doxyfile b/doc/Doxyfile
index 20fd00c..4db428c 100644
--- a/doc/Doxyfile
+++ b/doc/Doxyfile
@@ -1,4 +1,4 @@
-# Doxyfile 1.8.8
+# Doxyfile 1.8.13
 
 # This file describes the settings to be used by the documentation system
 # doxygen (www.doxygen.org) for a project.
@@ -46,10 +46,10 @@ PROJECT_NUMBER         =
 
 PROJECT_BRIEF          =
 
-# With the PROJECT_LOGO tag one can specify an logo or icon that is included in
-# the documentation. The maximum height of the logo should not exceed 55 pixels
-# and the maximum width should not exceed 200 pixels. Doxygen will copy the logo
-# to the output directory.
+# With the PROJECT_LOGO tag one can specify a logo or an icon that is included
+# in the documentation. The maximum height of the logo should not exceed 55
+# pixels and the maximum width should not exceed 200 pixels. Doxygen will copy
+# the logo to the output directory.
 
 PROJECT_LOGO           =
 
@@ -60,7 +60,7 @@ PROJECT_LOGO           =
 
 OUTPUT_DIRECTORY       = doc/doxygen
 
-# If the CREATE_SUBDIRS tag is set to YES, then doxygen will create 4096 sub-
+# If the CREATE_SUBDIRS tag is set to YES then doxygen will create 4096 sub-
 # directories (in 2 levels) under the output directory of each output format and
 # will distribute the generated files over these directories. Enabling this
 # option can be useful when feeding doxygen a huge amount of source files, where
@@ -76,7 +76,7 @@ CREATE_SUBDIRS         = NO
 # U+3044.
 # The default value is: NO.
 
-#ALLOW_UNICODE_NAMES    = NO
+ALLOW_UNICODE_NAMES    = NO
 
 # The OUTPUT_LANGUAGE tag is used to specify the language in which all
 # documentation generated by doxygen is written. Doxygen will use this
@@ -93,14 +93,14 @@ CREATE_SUBDIRS         = NO
 
 OUTPUT_LANGUAGE        = English
 
-# If the BRIEF_MEMBER_DESC tag is set to YES doxygen will include brief member
+# If the BRIEF_MEMBER_DESC tag is set to YES, doxygen will include brief member
 # descriptions after the members that are listed in the file and class
 # documentation (similar to Javadoc). Set to NO to disable this.
 # The default value is: YES.
 
 BRIEF_MEMBER_DESC      = YES
 
-# If the REPEAT_BRIEF tag is set to YES doxygen will prepend the brief
+# If the REPEAT_BRIEF tag is set to YES, doxygen will prepend the brief
 # description of a member or function before the detailed description
 #
 # Note: If both HIDE_UNDOC_MEMBERS and BRIEF_MEMBER_DESC are set to NO, the
@@ -135,7 +135,7 @@ ALWAYS_DETAILED_SEC    = NO
 
 INLINE_INHERITED_MEMB  = NO
 
-# If the FULL_PATH_NAMES tag is set to YES doxygen will prepend the full path
+# If the FULL_PATH_NAMES tag is set to YES, doxygen will prepend the full path
 # before files name in the file list and in the header files. If set to NO the
 # shortest path that makes the file name unique will be used
 # The default value is: YES.
@@ -205,9 +205,9 @@ MULTILINE_CPP_IS_BRIEF = NO
 
 INHERIT_DOCS           = YES
 
-# If the SEPARATE_MEMBER_PAGES tag is set to YES, then doxygen will produce a
-# new page for each member. If set to NO, the documentation of a member will be
-# part of the file/class/namespace that contains it.
+# If the SEPARATE_MEMBER_PAGES tag is set to YES then doxygen will produce a new
+# page for each member. If set to NO, the documentation of a member will be part
+# of the file/class/namespace that contains it.
 # The default value is: NO.
 
 SEPARATE_MEMBER_PAGES  = NO
@@ -230,6 +230,11 @@ TAB_SIZE               = 8
 
 ALIASES                =
 
+# This tag can be used to specify a number of word-keyword mappings (TCL only).
+# A mapping has the form "name=value". For example adding "class=itcl::class"
+# will allow you to use the command class in the itcl::class meaning.
+
+TCL_SUBST              =
 
 # Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C sources
 # only. Doxygen will then generate output that is more tailored for C. For
@@ -271,7 +276,7 @@ OPTIMIZE_OUTPUT_VHDL   = NO
 # instance to make doxygen treat .inc files as Fortran files (default is PHP),
 # and .f files as C (default is Fortran), use: inc=Fortran f=C.
 #
-# Note For files without extension you can use no_extension as a placeholder.
+# Note: For files without extension you can use no_extension as a placeholder.
 #
 # Note that for custom extensions you also need to set FILE_PATTERNS otherwise
 # the files are not read by doxygen.
@@ -286,15 +291,24 @@ EXTENSION_MAPPING      =
 # case of backward compatibilities issues.
 # The default value is: YES.
 
-#MARKDOWN_SUPPORT       = YES
+MARKDOWN_SUPPORT       = YES
+
+# When the TOC_INCLUDE_HEADINGS tag is set to a non-zero value, all headings up
+# to that level are automatically included in the table of contents, even if
+# they do not have an id attribute.
+# Note: This feature currently applies only to Markdown headings.
+# Minimum value: 0, maximum value: 99, default value: 0.
+# This tag requires that the tag MARKDOWN_SUPPORT is set to YES.
+
+TOC_INCLUDE_HEADINGS   = 0
 
 # When enabled doxygen tries to link words that correspond to documented
 # classes, or namespaces to their corresponding documentation. Such a link can
-# be prevented in individual cases by by putting a % sign in front of the word
-# or globally by setting AUTOLINK_SUPPORT to NO.
+# be prevented in individual cases by putting a % sign in front of the word or
+# globally by setting AUTOLINK_SUPPORT to NO.
 # The default value is: YES.
 
-#AUTOLINK_SUPPORT       = YES
+AUTOLINK_SUPPORT       = YES
 
 # If you use STL classes (i.e. std::string, std::vector, etc.) but do not want
 # to include (a tag file for) the STL sources as input, then you should set this
@@ -331,13 +345,20 @@ SIP_SUPPORT            = NO
 IDL_PROPERTY_SUPPORT   = YES
 
 # If member grouping is used in the documentation and the DISTRIBUTE_GROUP_DOC
-# tag is set to YES, then doxygen will reuse the documentation of the first
+# tag is set to YES then doxygen will reuse the documentation of the first
 # member in the group (if any) for the other members of the group. By default
 # all members of a group must be documented explicitly.
 # The default value is: NO.
 
 DISTRIBUTE_GROUP_DOC   = NO
 
+# If one adds a struct or class to a group and this option is enabled, then also
+# any nested class or struct is added to the same group. By default this option
+# is disabled and one has to add nested compounds explicitly via \ingroup.
+# The default value is: NO.
+
+GROUP_NESTED_COMPOUNDS = NO
+
 # Set the SUBGROUPING tag to YES to allow class member groups of the same type
 # (for instance a group of public functions) to be put as a subgroup of that
 # type (e.g. under the Public Functions section). Set it to NO to prevent
@@ -396,7 +417,7 @@ LOOKUP_CACHE_SIZE      = 0
 # Build related configuration options
 #---------------------------------------------------------------------------
 
-# If the EXTRACT_ALL tag is set to YES doxygen will assume all entities in
+# If the EXTRACT_ALL tag is set to YES, doxygen will assume all entities in
 # documentation are documented, even if no documentation was available. Private
 # class members and static file members will be hidden unless the
 # EXTRACT_PRIVATE respectively EXTRACT_STATIC tags are set to YES.
@@ -404,37 +425,37 @@ LOOKUP_CACHE_SIZE      = 0
 # normally produced when WARNINGS is set to YES.
 # The default value is: NO.
 
-EXTRACT_ALL            = YES
+EXTRACT_ALL            = NO
 
-# If the EXTRACT_PRIVATE tag is set to YES all private members of a class will
+# If the EXTRACT_PRIVATE tag is set to YES, all private members of a class will
 # be included in the documentation.
 # The default value is: NO.
 
 EXTRACT_PRIVATE        = NO
 
-# If the EXTRACT_PACKAGE tag is set to YES all members with package or internal
+# If the EXTRACT_PACKAGE tag is set to YES, all members with package or internal
 # scope will be included in the documentation.
 # The default value is: NO.
 
-#EXTRACT_PACKAGE        = NO
+EXTRACT_PACKAGE        = NO
 
-# If the EXTRACT_STATIC tag is set to YES all static members of a file will be
+# If the EXTRACT_STATIC tag is set to YES, all static members of a file will be
 # included in the documentation.
 # The default value is: NO.
 
 EXTRACT_STATIC         = NO
 
-# If the EXTRACT_LOCAL_CLASSES tag is set to YES classes (and structs) defined
-# locally in source files will be included in the documentation. If set to NO
+# If the EXTRACT_LOCAL_CLASSES tag is set to YES, classes (and structs) defined
+# locally in source files will be included in the documentation. If set to NO,
 # only classes defined in header files are included. Does not have any effect
 # for Java sources.
 # The default value is: YES.
 
 EXTRACT_LOCAL_CLASSES  = YES
 
-# This flag is only useful for Objective-C code. When set to YES local methods,
+# This flag is only useful for Objective-C code. If set to YES, local methods,
 # which are defined in the implementation section but not in the interface are
-# included in the documentation. If set to NO only methods in the interface are
+# included in the documentation. If set to NO, only methods in the interface are
 # included.
 # The default value is: NO.
 
@@ -459,21 +480,21 @@ HIDE_UNDOC_MEMBERS     = NO
 
 # If the HIDE_UNDOC_CLASSES tag is set to YES, doxygen will hide all
 # undocumented classes that are normally visible in the class hierarchy. If set
-# to NO these classes will be included in the various overviews. This option has
-# no effect if EXTRACT_ALL is enabled.
+# to NO, these classes will be included in the various overviews. This option
+# has no effect if EXTRACT_ALL is enabled.
 # The default value is: NO.
 
 HIDE_UNDOC_CLASSES     = NO
 
 # If the HIDE_FRIEND_COMPOUNDS tag is set to YES, doxygen will hide all friend
-# (class|struct|union) declarations. If set to NO these declarations will be
+# (class|struct|union) declarations. If set to NO, these declarations will be
 # included in the documentation.
 # The default value is: NO.
 
 HIDE_FRIEND_COMPOUNDS  = NO
 
 # If the HIDE_IN_BODY_DOCS tag is set to YES, doxygen will hide any
-# documentation blocks found inside the body of a function. If set to NO these
+# documentation blocks found inside the body of a function. If set to NO, these
 # blocks will be appended to the function's detailed documentation block.
 # The default value is: NO.
 
@@ -487,7 +508,7 @@ HIDE_IN_BODY_DOCS      = NO
 INTERNAL_DOCS          = NO
 
 # If the CASE_SENSE_NAMES tag is set to NO then doxygen will only generate file
-# names in lower-case letters. If set to YES upper-case letters are also
+# names in lower-case letters. If set to YES, upper-case letters are also
 # allowed. This is useful if you have classes or files whose names only differ
 # in case and if your file system supports case sensitive file names. Windows
 # and Mac users are advised to set this option to NO.
@@ -496,12 +517,19 @@ INTERNAL_DOCS          = NO
 CASE_SENSE_NAMES       = YES
 
 # If the HIDE_SCOPE_NAMES tag is set to NO then doxygen will show members with
-# their full class and namespace scopes in the documentation. If set to YES the
+# their full class and namespace scopes in the documentation. If set to YES, the
 # scope will be hidden.
 # The default value is: NO.
 
 HIDE_SCOPE_NAMES       = NO
 
+# If the HIDE_COMPOUND_REFERENCE tag is set to NO (default) then doxygen will
+# append additional text to a page's title, such as Class Reference. If set to
+# YES the compound reference will be hidden.
+# The default value is: NO.
+
+HIDE_COMPOUND_REFERENCE= NO
+
 # If the SHOW_INCLUDE_FILES tag is set to YES then doxygen will put a list of
 # the files that are included by a file in the documentation of that file.
 # The default value is: YES.
@@ -513,7 +541,7 @@ SHOW_INCLUDE_FILES     = YES
 # which file to include in order to use the member.
 # The default value is: NO.
 
-#SHOW_GROUPED_MEMB_INC  = NO
+SHOW_GROUPED_MEMB_INC  = NO
 
 # If the FORCE_LOCAL_INCLUDES tag is set to YES then doxygen will list include
 # files with double quotes in the documentation rather than with sharp brackets.
@@ -529,14 +557,14 @@ INLINE_INFO            = YES
 
 # If the SORT_MEMBER_DOCS tag is set to YES then doxygen will sort the
 # (detailed) documentation of file and class members alphabetically by member
-# name. If set to NO the members will appear in declaration order.
+# name. If set to NO, the members will appear in declaration order.
 # The default value is: YES.
 
 SORT_MEMBER_DOCS       = YES
 
 # If the SORT_BRIEF_DOCS tag is set to YES then doxygen will sort the brief
 # descriptions of file, namespace and class members alphabetically by member
-# name. If set to NO the members will appear in declaration order. Note that
+# name. If set to NO, the members will appear in declaration order. Note that
 # this will also influence the order of the classes in the class list.
 # The default value is: NO.
 
@@ -581,27 +609,25 @@ SORT_BY_SCOPE_NAME     = NO
 
 STRICT_PROTO_MATCHING  = NO
 
-# The GENERATE_TODOLIST tag can be used to enable ( YES) or disable ( NO) the
-# todo list. This list is created by putting \todo commands in the
-# documentation.
+# The GENERATE_TODOLIST tag can be used to enable (YES) or disable (NO) the todo
+# list. This list is created by putting \todo commands in the documentation.
 # The default value is: YES.
 
 GENERATE_TODOLIST      = YES
 
-# The GENERATE_TESTLIST tag can be used to enable ( YES) or disable ( NO) the
-# test list. This list is created by putting \test commands in the
-# documentation.
+# The GENERATE_TESTLIST tag can be used to enable (YES) or disable (NO) the test
+# list. This list is created by putting \test commands in the documentation.
 # The default value is: YES.
 
 GENERATE_TESTLIST      = YES
 
-# The GENERATE_BUGLIST tag can be used to enable ( YES) or disable ( NO) the bug
+# The GENERATE_BUGLIST tag can be used to enable (YES) or disable (NO) the bug
 # list. This list is created by putting \bug commands in the documentation.
 # The default value is: YES.
 
 GENERATE_BUGLIST       = YES
 
-# The GENERATE_DEPRECATEDLIST tag can be used to enable ( YES) or disable ( NO)
+# The GENERATE_DEPRECATEDLIST tag can be used to enable (YES) or disable (NO)
 # the deprecated list. This list is created by putting \deprecated commands in
 # the documentation.
 # The default value is: YES.
@@ -626,8 +652,8 @@ ENABLED_SECTIONS       =
 MAX_INITIALIZER_LINES  = 30
 
 # Set the SHOW_USED_FILES tag to NO to disable the list of files generated at
-# the bottom of the documentation of classes and structs. If set to YES the list
-# will mention the files that were used to generate the documentation.
+# the bottom of the documentation of classes and structs. If set to YES, the
+# list will mention the files that were used to generate the documentation.
 # The default value is: YES.
 
 SHOW_USED_FILES        = YES
@@ -691,7 +717,7 @@ CITE_BIB_FILES         =
 QUIET                  = NO
 
 # The WARNINGS tag can be used to turn on/off the warning messages that are
-# generated to standard error ( stderr) by doxygen. If WARNINGS is set to YES
+# generated to standard error (stderr) by doxygen. If WARNINGS is set to YES
 # this implies that the warnings are on.
 #
 # Tip: Turn warnings on while writing the documentation.
@@ -699,7 +725,7 @@ QUIET                  = NO
 
 WARNINGS               = YES
 
-# If the WARN_IF_UNDOCUMENTED tag is set to YES, then doxygen will generate
+# If the WARN_IF_UNDOCUMENTED tag is set to YES then doxygen will generate
 # warnings for undocumented members. If EXTRACT_ALL is set to YES then this flag
 # will automatically be disabled.
 # The default value is: YES.
@@ -716,11 +742,17 @@ WARN_IF_DOC_ERROR      = YES
 
 # This WARN_NO_PARAMDOC option can be enabled to get warnings for functions that
 # are documented, but have no documentation for their parameters or return
-# value. If set to NO doxygen will only warn about wrong or incomplete parameter
-# documentation, but not about the absence of documentation.
+# value. If set to NO, doxygen will only warn about wrong or incomplete
+# parameter documentation, but not about the absence of documentation.
+# The default value is: NO.
+
+WARN_NO_PARAMDOC       = NO
+
+# If the WARN_AS_ERROR tag is set to YES then doxygen will immediately stop when
+# a warning is encountered.
 # The default value is: NO.
 
-WARN_NO_PARAMDOC       = YES
+WARN_AS_ERROR          = NO
 
 # The WARN_FORMAT tag determines the format of the warning messages that doxygen
 # can produce. The string should contain the $file, $line, and $text tags, which
@@ -745,10 +777,10 @@ WARN_LOGFILE           =
 # The INPUT tag is used to specify the files and/or directories that contain
 # documented source files. You may enter file names like myfile.cpp or
 # directories like /usr/src/myproject. Separate the files or directories with
-# spaces.
+# spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
 # Note: If this tag is empty the current directory is searched.
 
-INPUT                  = include/dmlc
+INPUT                  = include
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses
@@ -761,14 +793,19 @@ INPUT_ENCODING         = UTF-8
 
 # If the value of the INPUT tag contains directories, you can use the
 # FILE_PATTERNS tag to specify one or more wildcard patterns (like *.cpp and
-# *.h) to filter out the source-files in the directories. If left blank the
-# following patterns are tested:*.c, *.cc, *.cxx, *.cpp, *.c++, *.java, *.ii,
-# *.ixx, *.ipp, *.i++, *.inl, *.idl, *.ddl, *.odl, *.h, *.hh, *.hxx, *.hpp,
-# *.h++, *.cs, *.d, *.php, *.php4, *.php5, *.phtml, *.inc, *.m, *.markdown,
-# *.md, *.mm, *.dox, *.py, *.f90, *.f, *.for, *.tcl, *.vhd, *.vhdl, *.ucf,
-# *.qsf, *.as and *.js.
+# *.h) to filter out the source-files in the directories.
+#
+# Note that for custom extensions or not directly supported extensions you also
+# need to set EXTENSION_MAPPING for the extension otherwise the files are not
+# read by doxygen.
+#
+# If left blank the following patterns are tested:*.c, *.cc, *.cxx, *.cpp,
+# *.c++, *.java, *.ii, *.ixx, *.ipp, *.i++, *.inl, *.idl, *.ddl, *.odl, *.h,
+# *.hh, *.hxx, *.hpp, *.h++, *.cs, *.d, *.php, *.php4, *.php5, *.phtml, *.inc,
+# *.m, *.markdown, *.md, *.mm, *.dox, *.py, *.pyw, *.f90, *.f95, *.f03, *.f08,
+# *.f, *.for, *.tcl, *.vhd, *.vhdl, *.ucf and *.qsf.
 
-FILE_PATTERNS          = *.h
+FILE_PATTERNS          =
 
 # The RECURSIVE tag can be used to specify whether or not subdirectories should
 # be searched for input files as well.
@@ -811,7 +848,7 @@ EXCLUDE_PATTERNS       = */test/* \
 # Note that the wildcards are matched against the file with absolute path, so to
 # exclude all test directories use the pattern */test/*
 
-EXCLUDE_SYMBOLS        = std
+EXCLUDE_SYMBOLS        =
 
 # The EXAMPLE_PATH tag can be used to specify one or more files or directories
 # that contain example code fragments that are included (see the \include
@@ -853,6 +890,10 @@ IMAGE_PATH             =
 # Note that the filter must not add or remove lines; it is applied before the
 # code is scanned, but not when the output code is generated. If lines are added
 # or removed, the anchors will not be placed correctly.
+#
+# Note that for custom extensions or not directly supported extensions you also
+# need to set EXTENSION_MAPPING for the extension otherwise the files are not
+# properly processed by doxygen.
 
 INPUT_FILTER           =
 
@@ -862,11 +903,15 @@ INPUT_FILTER           =
 # (like *.cpp=my_cpp_filter). See INPUT_FILTER for further information on how
 # filters are used. If the FILTER_PATTERNS tag is empty or if none of the
 # patterns match the file name, INPUT_FILTER is applied.
+#
+# Note that for custom extensions or not directly supported extensions you also
+# need to set EXTENSION_MAPPING for the extension otherwise the files are not
+# properly processed by doxygen.
 
 FILTER_PATTERNS        =
 
 # If the FILTER_SOURCE_FILES tag is set to YES, the input filter (if set using
-# INPUT_FILTER ) will also be used to filter the input files that are used for
+# INPUT_FILTER) will also be used to filter the input files that are used for
 # producing the source files to browse (i.e. when SOURCE_BROWSER is set to YES).
 # The default value is: NO.
 
@@ -885,7 +930,7 @@ FILTER_SOURCE_PATTERNS =
 # (index.html). This can be useful if you have a project on for instance GitHub
 # and want to reuse the introduction page also for the doxygen output.
 
-#USE_MDFILE_AS_MAINPAGE =
+USE_MDFILE_AS_MAINPAGE =
 
 #---------------------------------------------------------------------------
 # Configuration options related to source browsing
@@ -926,7 +971,7 @@ REFERENCED_BY_RELATION = NO
 REFERENCES_RELATION    = NO
 
 # If the REFERENCES_LINK_SOURCE tag is set to YES and SOURCE_BROWSER tag is set
-# to YES, then the hyperlinks from functions in REFERENCES_RELATION and
+# to YES then the hyperlinks from functions in REFERENCES_RELATION and
 # REFERENCED_BY_RELATION lists will link to the source code. Otherwise they will
 # link to the documentation.
 # The default value is: YES.
@@ -941,7 +986,7 @@ REFERENCES_LINK_SOURCE = YES
 # The default value is: YES.
 # This tag requires that the tag SOURCE_BROWSER is set to YES.
 
-#SOURCE_TOOLTIPS        = YES
+SOURCE_TOOLTIPS        = YES
 
 # If the USE_HTAGS tag is set to YES then the references to source code will
 # point to the HTML generated by the htags(1) tool instead of doxygen built-in
@@ -973,25 +1018,6 @@ USE_HTAGS              = NO
 
 VERBATIM_HEADERS       = YES
 
-# If the CLANG_ASSISTED_PARSING tag is set to YES, then doxygen will use the
-# clang parser (see: http://clang.llvm.org/) for more accurate parsing at the
-# cost of reduced performance. This can be particularly helpful with template
-# rich C++ code for which doxygen's built-in parser lacks the necessary type
-# information.
-# Note: The availability of this option depends on whether or not doxygen was
-# compiled with the --with-libclang option.
-# The default value is: NO.
-
-#CLANG_ASSISTED_PARSING = NO
-
-# If clang assisted parsing is enabled you can provide the compiler with command
-# line options that you would normally use when invoking the compiler. Note that
-# the include paths will already be set by doxygen for the files and directories
-# specified with INPUT and INCLUDE_PATH.
-# This tag requires that the tag CLANG_ASSISTED_PARSING is set to YES.
-
-#CLANG_OPTIONS          =
-
 #---------------------------------------------------------------------------
 # Configuration options related to the alphabetical class index
 #---------------------------------------------------------------------------
@@ -1022,7 +1048,7 @@ IGNORE_PREFIX          =
 # Configuration options related to the HTML output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_HTML tag is set to YES doxygen will generate HTML output
+# If the GENERATE_HTML tag is set to YES, doxygen will generate HTML output
 # The default value is: YES.
 
 GENERATE_HTML          = YES
@@ -1088,14 +1114,14 @@ HTML_STYLESHEET        =
 # cascading style sheets that are included after the standard style sheets
 # created by doxygen. Using this option one can overrule certain style aspects.
 # This is preferred over using HTML_STYLESHEET since it does not replace the
-# standard style sheet and is therefor more robust against future updates.
+# standard style sheet and is therefore more robust against future updates.
 # Doxygen will copy the style sheet files to the output directory.
-# Note: The order of the extra stylesheet files is of importance (e.g. the last
-# stylesheet in the list overrules the setting of the previous ones in the
+# Note: The order of the extra style sheet files is of importance (e.g. the last
+# style sheet in the list overrules the setting of the previous ones in the
 # list). For an example see the documentation.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-#HTML_EXTRA_STYLESHEET  =
+HTML_EXTRA_STYLESHEET  =
 
 # The HTML_EXTRA_FILES tag can be used to specify one or more extra images or
 # other source files which should be copied to the HTML output directory. Note
@@ -1108,7 +1134,7 @@ HTML_STYLESHEET        =
 HTML_EXTRA_FILES       =
 
 # The HTML_COLORSTYLE_HUE tag controls the color of the HTML output. Doxygen
-# will adjust the colors in the stylesheet and background images according to
+# will adjust the colors in the style sheet and background images according to
 # this color. Hue is specified as an angle on a colorwheel, see
 # http://en.wikipedia.org/wiki/Hue for more information. For instance the value
 # 0 represents red, 60 is yellow, 120 is green, 180 is cyan, 240 is blue, 300
@@ -1139,11 +1165,12 @@ HTML_COLORSTYLE_GAMMA  = 80
 
 # If the HTML_TIMESTAMP tag is set to YES then the footer of each generated HTML
 # page will contain the date and time when the page was generated. Setting this
-# to NO can help when comparing the output of multiple runs.
-# The default value is: YES.
+# to YES can help to show when doxygen was last run and thus if the
+# documentation is up to date.
+# The default value is: NO.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-HTML_TIMESTAMP         = NO
+HTML_TIMESTAMP         = YES
 
 # If the HTML_DYNAMIC_SECTIONS tag is set to YES then the generated HTML
 # documentation will contain sections that can be hidden and shown after the
@@ -1164,7 +1191,7 @@ HTML_DYNAMIC_SECTIONS  = NO
 # Minimum value: 0, maximum value: 9999, default value: 100.
 # This tag requires that the tag GENERATE_HTML is set to YES.
 
-#HTML_INDEX_NUM_ENTRIES = 100
+HTML_INDEX_NUM_ENTRIES = 100
 
 # If the GENERATE_DOCSET tag is set to YES, additional index files will be
 # generated that can be used as input for Apple's Xcode 3 integrated development
@@ -1236,28 +1263,28 @@ GENERATE_HTMLHELP      = NO
 CHM_FILE               =
 
 # The HHC_LOCATION tag can be used to specify the location (absolute path
-# including file name) of the HTML help compiler ( hhc.exe). If non-empty
+# including file name) of the HTML help compiler (hhc.exe). If non-empty,
 # doxygen will try to run the HTML help compiler on the generated index.hhp.
 # The file has to be specified with full path.
 # This tag requires that the tag GENERATE_HTMLHELP is set to YES.
 
 HHC_LOCATION           =
 
-# The GENERATE_CHI flag controls if a separate .chi index file is generated (
-# YES) or that it should be included in the master .chm file ( NO).
+# The GENERATE_CHI flag controls if a separate .chi index file is generated
+# (YES) or that it should be included in the master .chm file (NO).
 # The default value is: NO.
 # This tag requires that the tag GENERATE_HTMLHELP is set to YES.
 
 GENERATE_CHI           = NO
 
-# The CHM_INDEX_ENCODING is used to encode HtmlHelp index ( hhk), content ( hhc)
+# The CHM_INDEX_ENCODING is used to encode HtmlHelp index (hhk), content (hhc)
 # and project file content.
 # This tag requires that the tag GENERATE_HTMLHELP is set to YES.
 
 CHM_INDEX_ENCODING     =
 
-# The BINARY_TOC flag controls whether a binary table of contents is generated (
-# YES) or a normal table of contents ( NO) in the .chm file. Furthermore it
+# The BINARY_TOC flag controls whether a binary table of contents is generated
+# (YES) or a normal table of contents (NO) in the .chm file. Furthermore it
 # enables the Previous and Next buttons.
 # The default value is: NO.
 # This tag requires that the tag GENERATE_HTMLHELP is set to YES.
@@ -1371,7 +1398,7 @@ DISABLE_INDEX          = NO
 # index structure (just like the one that is generated for HTML Help). For this
 # to work a browser that supports JavaScript, DHTML, CSS and frames is required
 # (i.e. any modern browser). Windows users are probably better off using the
-# HTML help feature. Via custom stylesheets (see HTML_EXTRA_STYLESHEET) one can
+# HTML help feature. Via custom style sheets (see HTML_EXTRA_STYLESHEET) one can
 # further fine-tune the look of the index. As an example, the default style
 # sheet generated by doxygen has an example that shows how to put an image at
 # the root of the tree instead of the PROJECT_NAME. Since the tree basically has
@@ -1399,7 +1426,7 @@ ENUM_VALUES_PER_LINE   = 4
 
 TREEVIEW_WIDTH         = 250
 
-# When the EXT_LINKS_IN_WINDOW option is set to YES doxygen will open links to
+# If the EXT_LINKS_IN_WINDOW option is set to YES, doxygen will open links to
 # external symbols imported via tag files in a separate window.
 # The default value is: NO.
 # This tag requires that the tag GENERATE_HTML is set to YES.
@@ -1428,7 +1455,7 @@ FORMULA_TRANSPARENT    = YES
 
 # Enable the USE_MATHJAX option to render LaTeX formulas using MathJax (see
 # http://www.mathjax.org) which uses client side Javascript for the rendering
-# instead of using prerendered bitmaps. Use this if you do not have LaTeX
+# instead of using pre-rendered bitmaps. Use this if you do not have LaTeX
 # installed or if you want to formulas look prettier in the HTML output. When
 # enabled you may also need to install MathJax separately and configure the path
 # to it using the MATHJAX_RELPATH option.
@@ -1445,7 +1472,7 @@ USE_MATHJAX            = NO
 # The default value is: HTML-CSS.
 # This tag requires that the tag USE_MATHJAX is set to YES.
 
-#MATHJAX_FORMAT         = HTML-CSS
+MATHJAX_FORMAT         = HTML-CSS
 
 # When MathJax is enabled you need to specify the location relative to the HTML
 # output directory using the MATHJAX_RELPATH option. The destination directory
@@ -1473,7 +1500,7 @@ MATHJAX_EXTENSIONS     =
 # example see the documentation.
 # This tag requires that the tag USE_MATHJAX is set to YES.
 
-#MATHJAX_CODEFILE       =
+MATHJAX_CODEFILE       =
 
 # When the SEARCHENGINE tag is enabled doxygen will generate a search box for
 # the HTML output. The underlying search engine uses javascript and DHTML and
@@ -1514,7 +1541,7 @@ SERVER_BASED_SEARCH    = NO
 # external search engine pointed to by the SEARCHENGINE_URL option to obtain the
 # search results.
 #
-# Doxygen ships with an example indexer ( doxyindexer) and search engine
+# Doxygen ships with an example indexer (doxyindexer) and search engine
 # (doxysearch.cgi) which are based on the open source search engine library
 # Xapian (see: http://xapian.org/).
 #
@@ -1522,18 +1549,18 @@ SERVER_BASED_SEARCH    = NO
 # The default value is: NO.
 # This tag requires that the tag SEARCHENGINE is set to YES.
 
-#EXTERNAL_SEARCH        = NO
+EXTERNAL_SEARCH        = NO
 
 # The SEARCHENGINE_URL should point to a search engine hosted by a web server
 # which will return the search results when EXTERNAL_SEARCH is enabled.
 #
-# Doxygen ships with an example indexer ( doxyindexer) and search engine
+# Doxygen ships with an example indexer (doxyindexer) and search engine
 # (doxysearch.cgi) which are based on the open source search engine library
 # Xapian (see: http://xapian.org/). See the section "External Indexing and
 # Searching" for details.
 # This tag requires that the tag SEARCHENGINE is set to YES.
 
-#SEARCHENGINE_URL       =
+SEARCHENGINE_URL       =
 
 # When SERVER_BASED_SEARCH and EXTERNAL_SEARCH are both enabled the unindexed
 # search data is written to a file for indexing by an external tool. With the
@@ -1541,7 +1568,7 @@ SERVER_BASED_SEARCH    = NO
 # The default file is: searchdata.xml.
 # This tag requires that the tag SEARCHENGINE is set to YES.
 
-#SEARCHDATA_FILE        = searchdata.xml
+SEARCHDATA_FILE        = searchdata.xml
 
 # When SERVER_BASED_SEARCH and EXTERNAL_SEARCH are both enabled the
 # EXTERNAL_SEARCH_ID tag can be used as an identifier for the project. This is
@@ -1549,7 +1576,7 @@ SERVER_BASED_SEARCH    = NO
 # projects and redirect the results back to the right project.
 # This tag requires that the tag SEARCHENGINE is set to YES.
 
-#EXTERNAL_SEARCH_ID     =
+EXTERNAL_SEARCH_ID     =
 
 # The EXTRA_SEARCH_MAPPINGS tag can be used to enable searching through doxygen
 # projects other than the one defined by this configuration file, but that are
@@ -1559,13 +1586,13 @@ SERVER_BASED_SEARCH    = NO
 # EXTRA_SEARCH_MAPPINGS = tagname1=loc1 tagname2=loc2 ...
 # This tag requires that the tag SEARCHENGINE is set to YES.
 
-#EXTRA_SEARCH_MAPPINGS  =
+EXTRA_SEARCH_MAPPINGS  =
 
 #---------------------------------------------------------------------------
 # Configuration options related to the LaTeX output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_LATEX tag is set to YES doxygen will generate LaTeX output.
+# If the GENERATE_LATEX tag is set to YES, doxygen will generate LaTeX output.
 # The default value is: YES.
 
 GENERATE_LATEX         = YES
@@ -1596,7 +1623,7 @@ LATEX_CMD_NAME         = latex
 
 MAKEINDEX_CMD_NAME     = makeindex
 
-# If the COMPACT_LATEX tag is set to YES doxygen generates more compact LaTeX
+# If the COMPACT_LATEX tag is set to YES, doxygen generates more compact LaTeX
 # documents. This may be useful for small projects and may help to save some
 # trees in general.
 # The default value is: NO.
@@ -1614,9 +1641,12 @@ COMPACT_LATEX          = NO
 PAPER_TYPE             = a4
 
 # The EXTRA_PACKAGES tag can be used to specify one or more LaTeX package names
-# that should be included in the LaTeX output. To get the times font for
-# instance you can specify
-# EXTRA_PACKAGES=times
+# that should be included in the LaTeX output. The package can be specified just
+# by its name or with the correct syntax as to be used with the LaTeX
+# \usepackage command. To get the times font for instance you can specify :
+# EXTRA_PACKAGES=times or EXTRA_PACKAGES={times}
+# To use the option intlimits with the amsmath package you can specify:
+# EXTRA_PACKAGES=[intlimits]{amsmath}
 # If left blank no extra packages will be included.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
@@ -1631,9 +1661,9 @@ EXTRA_PACKAGES         =
 # Note: Only use a user-defined header if you know what you are doing! The
 # following commands have a special meaning inside the header: $title,
 # $datetime, $date, $doxygenversion, $projectname, $projectnumber,
-# $projectbrief, $projectlogo. Doxygen will replace $title with the empy string,
-# for the replacement values of the other commands the user is refered to
-# HTML_HEADER.
+# $projectbrief, $projectlogo. Doxygen will replace $title with the empty
+# string, for the replacement values of the other commands the user is referred
+# to HTML_HEADER.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
 LATEX_HEADER           =
@@ -1649,13 +1679,24 @@ LATEX_HEADER           =
 
 LATEX_FOOTER           =
 
+# The LATEX_EXTRA_STYLESHEET tag can be used to specify additional user-defined
+# LaTeX style sheets that are included after the standard style sheets created
+# by doxygen. Using this option one can overrule certain style aspects. Doxygen
+# will copy the style sheet files to the output directory.
+# Note: The order of the extra style sheet files is of importance (e.g. the last
+# style sheet in the list overrules the setting of the previous ones in the
+# list).
+# This tag requires that the tag GENERATE_LATEX is set to YES.
+
+LATEX_EXTRA_STYLESHEET =
+
 # The LATEX_EXTRA_FILES tag can be used to specify one or more extra images or
 # other source files which should be copied to the LATEX_OUTPUT output
 # directory. Note that the files will be copied as-is; there are no commands or
 # markers available.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
-#LATEX_EXTRA_FILES      =
+LATEX_EXTRA_FILES      =
 
 # If the PDF_HYPERLINKS tag is set to YES, the LaTeX that is generated is
 # prepared for conversion to PDF (using ps2pdf or pdflatex). The PDF file will
@@ -1667,7 +1708,7 @@ LATEX_FOOTER           =
 PDF_HYPERLINKS         = YES
 
 # If the USE_PDFLATEX tag is set to YES, doxygen will use pdflatex to generate
-# the PDF file directly from the LaTeX files. Set this option to YES to get a
+# the PDF file directly from the LaTeX files. Set this option to YES, to get a
 # higher quality PDF documentation.
 # The default value is: YES.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
@@ -1708,11 +1749,19 @@ LATEX_SOURCE_CODE      = NO
 
 LATEX_BIB_STYLE        = plain
 
+# If the LATEX_TIMESTAMP tag is set to YES then the footer of each generated
+# page will contain the date and time when the page was generated. Setting this
+# to NO can help when comparing the output of multiple runs.
+# The default value is: NO.
+# This tag requires that the tag GENERATE_LATEX is set to YES.
+
+LATEX_TIMESTAMP        = NO
+
 #---------------------------------------------------------------------------
 # Configuration options related to the RTF output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_RTF tag is set to YES doxygen will generate RTF output. The
+# If the GENERATE_RTF tag is set to YES, doxygen will generate RTF output. The
 # RTF output is optimized for Word 97 and may not look too pretty with other RTF
 # readers/editors.
 # The default value is: NO.
@@ -1727,7 +1776,7 @@ GENERATE_RTF           = NO
 
 RTF_OUTPUT             = rtf
 
-# If the COMPACT_RTF tag is set to YES doxygen generates more compact RTF
+# If the COMPACT_RTF tag is set to YES, doxygen generates more compact RTF
 # documents. This may be useful for small projects and may help to save some
 # trees in general.
 # The default value is: NO.
@@ -1764,11 +1813,21 @@ RTF_STYLESHEET_FILE    =
 
 RTF_EXTENSIONS_FILE    =
 
+# If the RTF_SOURCE_CODE tag is set to YES then doxygen will include source code
+# with syntax highlighting in the RTF output.
+#
+# Note that which sources are shown also depends on other settings such as
+# SOURCE_BROWSER.
+# The default value is: NO.
+# This tag requires that the tag GENERATE_RTF is set to YES.
+
+RTF_SOURCE_CODE        = NO
+
 #---------------------------------------------------------------------------
 # Configuration options related to the man page output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_MAN tag is set to YES doxygen will generate man pages for
+# If the GENERATE_MAN tag is set to YES, doxygen will generate man pages for
 # classes and files.
 # The default value is: NO.
 
@@ -1797,7 +1856,7 @@ MAN_EXTENSION          = .3
 # MAN_EXTENSION with the initial . removed.
 # This tag requires that the tag GENERATE_MAN is set to YES.
 
-#MAN_SUBDIR             =
+MAN_SUBDIR             =
 
 # If the MAN_LINKS tag is set to YES and doxygen generates man output, then it
 # will generate one additional man file for each entity documented in the real
@@ -1812,7 +1871,7 @@ MAN_LINKS              = NO
 # Configuration options related to the XML output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_XML tag is set to YES doxygen will generate an XML file that
+# If the GENERATE_XML tag is set to YES, doxygen will generate an XML file that
 # captures the structure of the code including all documentation.
 # The default value is: NO.
 
@@ -1826,7 +1885,7 @@ GENERATE_XML           = YES
 
 XML_OUTPUT             = xml
 
-# If the XML_PROGRAMLISTING tag is set to YES doxygen will dump the program
+# If the XML_PROGRAMLISTING tag is set to YES, doxygen will dump the program
 # listings (including syntax highlighting and cross-referencing information) to
 # the XML output. Note that enabling this will significantly increase the size
 # of the XML output.
@@ -1839,11 +1898,11 @@ XML_PROGRAMLISTING     = YES
 # Configuration options related to the DOCBOOK output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_DOCBOOK tag is set to YES doxygen will generate Docbook files
+# If the GENERATE_DOCBOOK tag is set to YES, doxygen will generate Docbook files
 # that can be used to generate PDF.
 # The default value is: NO.
 
-#GENERATE_DOCBOOK       = NO
+GENERATE_DOCBOOK       = NO
 
 # The DOCBOOK_OUTPUT tag is used to specify where the Docbook pages will be put.
 # If a relative path is entered the value of OUTPUT_DIRECTORY will be put in
@@ -1851,25 +1910,25 @@ XML_PROGRAMLISTING     = YES
 # The default directory is: docbook.
 # This tag requires that the tag GENERATE_DOCBOOK is set to YES.
 
-#DOCBOOK_OUTPUT         = docbook
+DOCBOOK_OUTPUT         = docbook
 
-# If the DOCBOOK_PROGRAMLISTING tag is set to YES doxygen will include the
+# If the DOCBOOK_PROGRAMLISTING tag is set to YES, doxygen will include the
 # program listings (including syntax highlighting and cross-referencing
 # information) to the DOCBOOK output. Note that enabling this will significantly
 # increase the size of the DOCBOOK output.
 # The default value is: NO.
 # This tag requires that the tag GENERATE_DOCBOOK is set to YES.
 
-#DOCBOOK_PROGRAMLISTING = NO
+DOCBOOK_PROGRAMLISTING = NO
 
 #---------------------------------------------------------------------------
 # Configuration options for the AutoGen Definitions output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_AUTOGEN_DEF tag is set to YES doxygen will generate an AutoGen
-# Definitions (see http://autogen.sf.net) file that captures the structure of
-# the code including all documentation. Note that this feature is still
-# experimental and incomplete at the moment.
+# If the GENERATE_AUTOGEN_DEF tag is set to YES, doxygen will generate an
+# AutoGen Definitions (see http://autogen.sf.net) file that captures the
+# structure of the code including all documentation. Note that this feature is
+# still experimental and incomplete at the moment.
 # The default value is: NO.
 
 GENERATE_AUTOGEN_DEF   = NO
@@ -1878,7 +1937,7 @@ GENERATE_AUTOGEN_DEF   = NO
 # Configuration options related to the Perl module output
 #---------------------------------------------------------------------------
 
-# If the GENERATE_PERLMOD tag is set to YES doxygen will generate a Perl module
+# If the GENERATE_PERLMOD tag is set to YES, doxygen will generate a Perl module
 # file that captures the structure of the code including all documentation.
 #
 # Note that this feature is still experimental and incomplete at the moment.
@@ -1886,7 +1945,7 @@ GENERATE_AUTOGEN_DEF   = NO
 
 GENERATE_PERLMOD       = NO
 
-# If the PERLMOD_LATEX tag is set to YES doxygen will generate the necessary
+# If the PERLMOD_LATEX tag is set to YES, doxygen will generate the necessary
 # Makefile rules, Perl scripts and LaTeX code to be able to generate PDF and DVI
 # output from the Perl module output.
 # The default value is: NO.
@@ -1894,9 +1953,9 @@ GENERATE_PERLMOD       = NO
 
 PERLMOD_LATEX          = NO
 
-# If the PERLMOD_PRETTY tag is set to YES the Perl module output will be nicely
+# If the PERLMOD_PRETTY tag is set to YES, the Perl module output will be nicely
 # formatted so it can be parsed by a human reader. This is useful if you want to
-# understand what is going on. On the other hand, if this tag is set to NO the
+# understand what is going on. On the other hand, if this tag is set to NO, the
 # size of the Perl module output will be much smaller and Perl will parse it
 # just the same.
 # The default value is: YES.
@@ -1916,20 +1975,20 @@ PERLMOD_MAKEVAR_PREFIX =
 # Configuration options related to the preprocessor
 #---------------------------------------------------------------------------
 
-# If the ENABLE_PREPROCESSING tag is set to YES doxygen will evaluate all
+# If the ENABLE_PREPROCESSING tag is set to YES, doxygen will evaluate all
 # C-preprocessor directives found in the sources and include files.
 # The default value is: YES.
 
-ENABLE_PREPROCESSING   = YES
+ENABLE_PREPROCESSING   = NO
 
-# If the MACRO_EXPANSION tag is set to YES doxygen will expand all macro names
-# in the source code. If set to NO only conditional compilation will be
+# If the MACRO_EXPANSION tag is set to YES, doxygen will expand all macro names
+# in the source code. If set to NO, only conditional compilation will be
 # performed. Macro expansion can be done in a controlled way by setting
 # EXPAND_ONLY_PREDEF to YES.
 # The default value is: NO.
 # This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
 
-MACRO_EXPANSION        = YES
+MACRO_EXPANSION        = NO
 
 # If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES then
 # the macro expansion is limited to the macros specified with the PREDEFINED and
@@ -1939,7 +1998,7 @@ MACRO_EXPANSION        = YES
 
 EXPAND_ONLY_PREDEF     = NO
 
-# If the SEARCH_INCLUDES tag is set to YES the includes files in the
+# If the SEARCH_INCLUDES tag is set to YES, the include files in the
 # INCLUDE_PATH will be searched if a #include is found.
 # The default value is: YES.
 # This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
@@ -1969,7 +2028,7 @@ INCLUDE_FILE_PATTERNS  =
 # recursively expanded use the := operator instead of the = operator.
 # This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
 
-PREDEFINED             = DMLC_USE_CXX11 TVM_DLL= __attribute__(x)=
+PREDEFINED             =
 
 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then this
 # tag can be used to specify a list of macro names that should be expanded. The
@@ -2015,31 +2074,32 @@ TAGFILES               =
 
 GENERATE_TAGFILE       =
 
-# If the ALLEXTERNALS tag is set to YES all external class will be listed in the
-# class index. If set to NO only the inherited external classes will be listed.
+# If the ALLEXTERNALS tag is set to YES, all external class will be listed in
+# the class index. If set to NO, only the inherited external classes will be
+# listed.
 # The default value is: NO.
 
 ALLEXTERNALS           = NO
 
-# If the EXTERNAL_GROUPS tag is set to YES all external groups will be listed in
-# the modules index. If set to NO, only the current project's groups will be
+# If the EXTERNAL_GROUPS tag is set to YES, all external groups will be listed
+# in the modules index. If set to NO, only the current project's groups will be
 # listed.
 # The default value is: YES.
 
 EXTERNAL_GROUPS        = YES
 
-# If the EXTERNAL_PAGES tag is set to YES all external pages will be listed in
+# If the EXTERNAL_PAGES tag is set to YES, all external pages will be listed in
 # the related pages index. If set to NO, only the current project's pages will
 # be listed.
 # The default value is: YES.
 
-#EXTERNAL_PAGES         = YES
+EXTERNAL_PAGES         = YES
 
 #---------------------------------------------------------------------------
 # Configuration options related to the dot tool
 #---------------------------------------------------------------------------
 
-# If the CLASS_DIAGRAMS tag is set to YES doxygen will generate a class diagram
+# If the CLASS_DIAGRAMS tag is set to YES, doxygen will generate a class diagram
 # (in HTML and LaTeX) for classes with base or super classes. Setting the tag to
 # NO turns the diagrams off. Note that this option also works with HAVE_DOT
 # disabled, but it is recommended to install and use dot, since it yields more
@@ -2053,9 +2113,9 @@ CLASS_DIAGRAMS         = YES
 # DIA_PATH tag allows you to specify the directory where the dia binary resides.
 # If left empty dia is assumed to be found in the default search path.
 
-#DIA_PATH               =
+DIA_PATH               =
 
-# If set to YES, the inheritance and collaboration graphs will hide inheritance
+# If set to YES the inheritance and collaboration graphs will hide inheritance
 # and usage relations if the target is undocumented or is not a class.
 # The default value is: YES.
 
@@ -2066,9 +2126,9 @@ HIDE_UNDOC_RELATIONS   = YES
 # http://www.graphviz.org/), a graph visualization toolkit from AT&T and Lucent
 # Bell Labs. The other options in this section have no effect if this option is
 # set to NO
-# The default value is: YES.
+# The default value is: NO.
 
-HAVE_DOT               = YES
+HAVE_DOT               = NO
 
 # The DOT_NUM_THREADS specifies the number of dot invocations doxygen is allowed
 # to run in parallel. When set to 0 doxygen will base this on the number of
@@ -2128,13 +2188,13 @@ COLLABORATION_GRAPH    = YES
 
 GROUP_GRAPHS           = YES
 
-# If the UML_LOOK tag is set to YES doxygen will generate inheritance and
+# If the UML_LOOK tag is set to YES, doxygen will generate inheritance and
 # collaboration diagrams in a style similar to the OMG's Unified Modeling
 # Language.
 # The default value is: NO.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-UML_LOOK               = YES
+UML_LOOK               = NO
 
 # If the UML_LOOK tag is enabled, the fields and methods are shown inside the
 # class node. If there are many fields or methods and many nodes the graph may
@@ -2147,7 +2207,7 @@ UML_LOOK               = YES
 # Minimum value: 0, maximum value: 100, default value: 10.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-#UML_LIMIT_NUM_FIELDS   = 10
+UML_LIMIT_NUM_FIELDS   = 10
 
 # If the TEMPLATE_RELATIONS tag is set to YES then the inheritance and
 # collaboration graphs will show the relations between templates and their
@@ -2180,7 +2240,8 @@ INCLUDED_BY_GRAPH      = YES
 #
 # Note that enabling this option will significantly increase the time of a run.
 # So in most cases it will be better to enable call graphs for selected
-# functions only using the \callgraph command.
+# functions only using the \callgraph command. Disabling a call graph can be
+# accomplished by means of the command \hidecallgraph.
 # The default value is: NO.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
@@ -2191,7 +2252,8 @@ CALL_GRAPH             = NO
 #
 # Note that enabling this option will significantly increase the time of a run.
 # So in most cases it will be better to enable caller graphs for selected
-# functions only using the \callergraph command.
+# functions only using the \callergraph command. Disabling a caller graph can be
+# accomplished by means of the command \hidecallergraph.
 # The default value is: NO.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
@@ -2214,17 +2276,19 @@ GRAPHICAL_HIERARCHY    = YES
 DIRECTORY_GRAPH        = YES
 
 # The DOT_IMAGE_FORMAT tag can be used to set the image format of the images
-# generated by dot.
+# generated by dot. For an explanation of the image formats see the section
+# output formats in the documentation of the dot tool (Graphviz (see:
+# http://www.graphviz.org/)).
 # Note: If you choose svg you need to set HTML_FILE_EXTENSION to xhtml in order
 # to make the SVG files visible in IE 9+ (other browsers do not have this
 # requirement).
-# Possible values are: png, png:cairo, png:cairo:cairo, png:cairo:gd, png:gd,
-# png:gd:gd, jpg, jpg:cairo, jpg:cairo:gd, jpg:gd, jpg:gd:gd, gif, gif:cairo,
-# gif:cairo:gd, gif:gd, gif:gd:gd and svg.
+# Possible values are: png, jpg, gif, svg, png:gd, png:gd:gd, png:cairo,
+# png:cairo:gd, png:cairo:cairo, png:cairo:gdiplus, png:gdiplus and
+# png:gdiplus:gdiplus.
 # The default value is: png.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_IMAGE_FORMAT       = svg
+DOT_IMAGE_FORMAT       = png
 
 # If DOT_IMAGE_FORMAT is set to svg, then this option can be set to YES to
 # enable generation of interactive SVG images that allow zooming and panning.
@@ -2261,16 +2325,25 @@ MSCFILE_DIRS           =
 # contain dia files that are included in the documentation (see the \diafile
 # command).
 
-#DIAFILE_DIRS           =
+DIAFILE_DIRS           =
 
 # When using plantuml, the PLANTUML_JAR_PATH tag should be used to specify the
 # path where java can find the plantuml.jar file. If left blank, it is assumed
 # PlantUML is not used or called during a preprocessing step. Doxygen will
 # generate a warning when it encounters a \startuml command in this case and
 # will not generate output for the diagram.
-# This tag requires that the tag HAVE_DOT is set to YES.
 
-#PLANTUML_JAR_PATH      =
+PLANTUML_JAR_PATH      =
+
+# When using plantuml, the PLANTUML_CFG_FILE tag can be used to specify a
+# configuration file for plantuml.
+
+PLANTUML_CFG_FILE      =
+
+# When using plantuml, the specified paths are searched for files specified by
+# the !include statement in a plantuml block.
+
+PLANTUML_INCLUDE_PATH  =
 
 # The DOT_GRAPH_MAX_NODES tag can be used to set the maximum number of nodes
 # that will be shown in the graph. If the number of nodes in a graph becomes
@@ -2308,7 +2381,7 @@ MAX_DOT_GRAPH_DEPTH    = 0
 
 DOT_TRANSPARENT        = NO
 
-# Set the DOT_MULTI_TARGETS tag to YES allow dot to generate multiple output
+# Set the DOT_MULTI_TARGETS tag to YES to allow dot to generate multiple output
 # files in one run (i.e. multiple -o and -T options on the command line). This
 # makes dot run faster, but since only newer versions of dot (>1.8.10) support
 # this, this feature is disabled by default.
@@ -2325,7 +2398,7 @@ DOT_MULTI_TARGETS      = YES
 
 GENERATE_LEGEND        = YES
 
-# If the DOT_CLEANUP tag is set to YES doxygen will remove the intermediate dot
+# If the DOT_CLEANUP tag is set to YES, doxygen will remove the intermediate dot
 # files that are used to generate the various graphs.
 # The default value is: YES.
 # This tag requires that the tag HAVE_DOT is set to YES.
diff --git a/include/dmlc/base.h b/include/dmlc/base.h
index 0527828..9ff4726 100644
--- a/include/dmlc/base.h
+++ b/include/dmlc/base.h
@@ -48,13 +48,6 @@
 #endif
 #endif
 
-/*!
- * \brief Whether to disable date message on the log.
- */
-#ifndef DMLC_LOG_NODATE
-#define DMLC_LOG_NODATE 0
-#endif
-
 /*! \brief whether compile with hdfs support */
 #ifndef DMLC_USE_HDFS
 #define DMLC_USE_HDFS 0
@@ -116,12 +109,12 @@
 #define DMLC_USE_FOPEN64 1
 #endif
 
-/// check if g++ is before 5.0
+/// check if g++ is before 4.6
 #if DMLC_USE_CXX11 && defined(__GNUC__) && !defined(__clang_version__)
-#if __GNUC__ < 5
-#pragma message("Will need g++-5.0 or higher to compile all"           \
+#if __GNUC__ == 4 && __GNUC_MINOR__ < 6
+#pragma message("Will need g++-4.6 or higher to compile all"           \
                 "the features in dmlc-core, "                           \
-                "compile without c++11, some features may be disabled")
+                "compile without c++0x, some features may be disabled")
 #undef DMLC_USE_CXX11
 #define DMLC_USE_CXX11 0
 #endif
@@ -236,20 +229,6 @@ typedef unsigned __int64 uint64_t;
 #define noexcept(a) noexcept_##a
 #endif
 
-#if defined(_MSC_VER)
-#define DMLC_NO_INLINE __declspec(noinline)
-#else
-#define DMLC_NO_INLINE __attribute__((noinline))
-#endif
-
-#if defined(__GNUC__) || defined(__clang__)
-#define DMLC_ALWAYS_INLINE inline __attribute__((__always_inline__))
-#elif defined(_MSC_VER)
-#define DMLC_ALWAYS_INLINE __forceinline
-#else
-#define DMLC_ALWAYS_INLINE inline
-#endif
-
 #if DMLC_USE_CXX11
 #define DMLC_THROW_EXCEPTION noexcept(false)
 #define DMLC_NO_EXCEPTION  noexcept(true)
diff --git a/include/dmlc/data.h b/include/dmlc/data.h
index 9447e09..a6ac19c 100644
--- a/include/dmlc/data.h
+++ b/include/dmlc/data.h
@@ -337,7 +337,7 @@ struct ParserFactoryReg
  * \param TypeName The typename of of the data.
  * \param FactoryFunction The factory function that creates the parser.
  *
- * \code
+ * \begincode
  *
  *  // define the factory function
  *  template<typename IndexType, typename DType = real_t>
diff --git a/include/dmlc/logging.h b/include/dmlc/logging.h
index 8287750..4c50184 100644
--- a/include/dmlc/logging.h
+++ b/include/dmlc/logging.h
@@ -162,26 +162,51 @@ inline bool DebugLoggingEnabled() {
   return state == 1;
 }
 
-#ifndef DMLC_GLOG_DEFINED
+class LogCheckError {
+ public:
+  LogCheckError() : str(nullptr) {}
+  explicit LogCheckError(const std::string& str_) : str(new std::string(str_)) {}
+  LogCheckError(const LogCheckError& other) = delete;
+  LogCheckError(LogCheckError&& other) : str(other.str) {
+    other.str = nullptr;
+  }
+  ~LogCheckError() { if (str != nullptr) delete str; }
+  operator bool() const { return str != nullptr; }
+  LogCheckError& operator=(const LogCheckError& other) = delete;
+  LogCheckError& operator=(LogCheckError&& other) = delete;
+  std::string* str;
+};
 
-template <typename X, typename Y>
-std::unique_ptr<std::string> LogCheckFormat(const X& x, const Y& y) {
-  std::ostringstream os;
-  os << " (" << x << " vs. " << y << ") "; /* CHECK_XX(x, y) requires x and y can be serialized to string. Use CHECK(x OP y) otherwise. NOLINT(*) */
-  // no std::make_unique until c++14
-  return std::unique_ptr<std::string>(new std::string(os.str()));
-}
+#ifndef DMLC_GLOG_DEFINED
 
-// This function allows us to ignore sign comparison in the right scope.
-#define DEFINE_CHECK_FUNC(name, op)                                                        \
-  template <typename X, typename Y>                                                        \
-  DMLC_ALWAYS_INLINE std::unique_ptr<std::string> LogCheck##name(const X& x, const Y& y) { \
-    if (x op y) return nullptr;                                                            \
-    return LogCheckFormat(x, y);                                                           \
-  }                                                                                        \
-  DMLC_ALWAYS_INLINE std::unique_ptr<std::string> LogCheck##name(int x, int y) {           \
-    return LogCheck##name<int, int>(x, y);                                                 \
+#ifndef _LIBCPP_SGX_NO_IOSTREAMS
+#define DEFINE_CHECK_FUNC(name, op)                               \
+  template <typename X, typename Y>                               \
+  inline LogCheckError LogCheck##name(const X& x, const Y& y) {   \
+    if (x op y) return LogCheckError();                           \
+    std::ostringstream os;                                        \
+    os << " (" << x << " vs. " << y << ") ";  /* CHECK_XX(x, y) requires x and y can be serialized to string. Use CHECK(x OP y) otherwise. NOLINT(*) */ \
+    return LogCheckError(os.str());                               \
+  }                                                               \
+  inline LogCheckError LogCheck##name(int x, int y) {             \
+    return LogCheck##name<int, int>(x, y);                        \
   }
+#else
+#define DEFINE_CHECK_FUNC(name, op)                               \
+  template <typename X, typename Y>                               \
+  inline LogCheckError LogCheck##name(const X& x, const Y& y) {   \
+    if (x op y) return LogCheckError();                           \
+    return LogCheckError("Error.");                               \
+  }                                                               \
+  inline LogCheckError LogCheck##name(int x, int y) {             \
+    return LogCheck##name<int, int>(x, y);                        \
+  }
+#endif
+
+#define CHECK_BINARY_OP(name, op, x, y)                               \
+  if (dmlc::LogCheckError _check_err = dmlc::LogCheck##name(x, y))    \
+    dmlc::LogMessageFatal(__FILE__, __LINE__).stream()                \
+      << "Check failed: " << #x " " #op " " #y << *(_check_err.str) << ": "
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wsign-compare"
@@ -193,11 +218,6 @@ DEFINE_CHECK_FUNC(_EQ, ==)
 DEFINE_CHECK_FUNC(_NE, !=)
 #pragma GCC diagnostic pop
 
-#define CHECK_BINARY_OP(name, op, x, y)                  \
-  if (auto __dmlc__log__err = dmlc::LogCheck##name(x, y))  \
-      dmlc::LogMessageFatal(__FILE__, __LINE__).stream() \
-        << "Check failed: " << #x " " #op " " #y << *__dmlc__log__err << ": "
-
 // Always-on checking
 #define CHECK(x)                                           \
   if (!(x))                                                \
@@ -285,7 +305,7 @@ class DateLogger {
 #endif
   }
   const char* HumanDate() {
-#if !defined(_LIBCPP_SGX_CONFIG) && DMLC_LOG_NODATE == 0
+#ifndef _LIBCPP_SGX_CONFIG
 #if defined(_MSC_VER)
     _strtime_s(buffer_, sizeof(buffer_));
 #else
@@ -300,10 +320,8 @@ class DateLogger {
     snprintf(buffer_, sizeof(buffer_), "%02d:%02d:%02d",
              pnow->tm_hour, pnow->tm_min, pnow->tm_sec);
 #endif
-    return buffer_;
-#else
-    return "";
 #endif  // _LIBCPP_SGX_CONFIG
+    return buffer_;
   }
 
  private:
@@ -406,42 +424,30 @@ class LogMessageFatal : public LogMessage {
 #else
 class LogMessageFatal {
  public:
-  LogMessageFatal(const char *file, int line) {
-    Entry::ThreadLocal()->Init(file, line);
+  LogMessageFatal(const char* file, int line) {
+    log_stream_ << "[" << pretty_date_.HumanDate() << "] " << file << ":"
+                << line << ": ";
   }
-  std::ostringstream &stream() { return Entry::ThreadLocal()->log_stream; }
-  DMLC_NO_INLINE ~LogMessageFatal() DMLC_THROW_EXCEPTION {
+  std::ostringstream &stream() { return log_stream_; }
+  ~LogMessageFatal() DMLC_THROW_EXCEPTION {
 #if DMLC_LOG_STACK_TRACE
-    Entry::ThreadLocal()->log_stream << "\n"
-                                     << StackTrace(1, LogStackTraceLevel())
-                                     << "\n";
+    log_stream_ << "\n" << StackTrace(1, LogStackTraceLevel()) << "\n";
 #endif
-    throw Entry::ThreadLocal()->Finalize();
-  }
 
- private:
-  struct Entry {
-    std::ostringstream log_stream;
-    DMLC_NO_INLINE void Init(const char *file, int line) {
-      DateLogger date;
-      log_stream.str("");
-      log_stream.clear();
-      log_stream << "[" << date.HumanDate() << "] " << file << ":" << line
-                 << ": ";
-    }
-    dmlc::Error Finalize() {
+    // throwing out of destructor is evil
+    // hopefully we can do it here
+    // also log the message before throw
 #if DMLC_LOG_BEFORE_THROW
-      LOG(ERROR) << log_stream.str();
+    LOG(ERROR) << log_stream_.str();
 #endif
-      return dmlc::Error(log_stream.str());
-    }
-    DMLC_NO_INLINE static Entry *ThreadLocal() {
-      static thread_local Entry *result = new Entry();
-      return result;
-    }
-  };
-  LogMessageFatal(const LogMessageFatal &);
-  void operator=(const LogMessageFatal &);
+    throw Error(log_stream_.str());
+  }
+
+ private:
+  std::ostringstream log_stream_;
+  DateLogger pretty_date_;
+  LogMessageFatal(const LogMessageFatal&);
+  void operator=(const LogMessageFatal&);
 };
 #endif
 
diff --git a/include/dmlc/omp.h b/include/dmlc/omp.h
index b447470..3b1cbe2 100644
--- a/include/dmlc/omp.h
+++ b/include/dmlc/omp.h
@@ -31,7 +31,6 @@ inline int omp_get_num_threads() __GOMP_NOTHROW { return 1; }
 inline int omp_get_max_threads() __GOMP_NOTHROW { return 1; }
 inline int omp_get_num_procs() __GOMP_NOTHROW { return 1; }
 inline void omp_set_num_threads(int nthread) __GOMP_NOTHROW {}
-inline int omp_in_parallel() __GOMP_NOTHROW { return 0; }
 #ifdef __cplusplus
 }
 #endif  // __cplusplus
diff --git a/include/dmlc/parameter.h b/include/dmlc/parameter.h
index 6c16e74..61f696c 100644
--- a/include/dmlc/parameter.h
+++ b/include/dmlc/parameter.h
@@ -171,17 +171,20 @@ struct Parameter {
    * \tparam Container container type
    *
    * \param kwargs map of keyword arguments, or vector of pairs
+   * \param out_changed (optional) Output whether any parameter is changed during update.
    *
    * \throw ParamError when something go wrong.
    * \return vector of pairs of unknown arguments.
    */
   template <typename Container>
   std::vector<std::pair<std::string, std::string> >
-  UpdateAllowUnknown(Container const& kwargs) {
+  UpdateAllowUnknown(Container const& kwargs, bool* out_changed = nullptr) {
     std::vector<std::pair<std::string, std::string> > unknown;
-    PType::__MANAGER__()->RunUpdate(static_cast<PType *>(this), kwargs.begin(),
-                                    kwargs.end(), parameter::kAllowUnknown,
-                                    &unknown, nullptr);
+    bool changed {false};
+    changed = PType::__MANAGER__()->RunUpdate(static_cast<PType*>(this),
+                                              kwargs.begin(), kwargs.end(),
+                                              parameter::kAllowUnknown, &unknown, nullptr);
+    if (out_changed) { *out_changed = changed; }
     return unknown;
   }
 
@@ -347,6 +350,12 @@ class FieldAccessEntry {
    * \param value the value to be set
    */
   virtual void Set(void *head, const std::string &value) const = 0;
+  /*!
+   * \brief See if new and old values are the same
+   * \param head the pointer to the head of the struct
+   * \param value the value to be set
+   */
+  virtual bool Same(void* head, const std::string& value) const = 0;
   // check if value is OK
   virtual void Check(void *head) const {}
   /*!
@@ -452,14 +461,18 @@ class ParamManager {
    * \throw ParamError when there is unknown argument and unknown_args == NULL, or required argument is missing.
    */
   template <typename RandomAccessIterator>
-  void RunUpdate(void *head,
+  bool RunUpdate(void *head,
                  RandomAccessIterator begin,
                  RandomAccessIterator end,
                  parameter::ParamInitOption option,
                  std::vector<std::pair<std::string, std::string> > *unknown_args,
                  std::set<FieldAccessEntry*>* selected_args = nullptr) const {
+    bool changed {false};
     for (RandomAccessIterator it = begin; it != end; ++it) {
       if (FieldAccessEntry *e = Find(it->first)) {
+        if (!e->Same(head, it->second)) {
+          changed = true;
+        }
         e->Set(head, it->second);
         e->Check(head);
         if (selected_args) {
@@ -485,6 +498,7 @@ class ParamManager {
         }
       }
     }
+    return changed;
   }
   /*!
    * \brief internal function to add entry to manager,
@@ -629,6 +643,20 @@ class FieldEntryBase : public FieldAccessEntry {
     }
   }
 
+  // Don't check this function for Undefined Behavior (UB), as the function
+  // reads from a possibly uninitialized field
+  DMLC_SUPPRESS_UBSAN
+  bool Same(void* head, std::string const& value) const override {
+    DType old = this->Get(head);
+    DType now;
+    std::istringstream is(value);
+    is >> now;
+    // don't require = operator
+    bool is_same = std::equal(
+        reinterpret_cast<char*>(&now), reinterpret_cast<char*>(&now) + sizeof(now),
+        reinterpret_cast<char*>(&old));
+    return is_same;
+  }
   std::string GetStringValue(void *head) const override {
     std::ostringstream os;
     PrintValue(os, this->Get(head));
diff --git a/include/dmlc/registry.h b/include/dmlc/registry.h
index 249088b..9cda806 100644
--- a/include/dmlc/registry.h
+++ b/include/dmlc/registry.h
@@ -280,7 +280,7 @@ class FunctionRegEntryBase {
  *  Use of this is optional as it will create an error when a file tag do not exist.
  *  An alternative solution is always ask user to enable --whole-archieve during static link.
  *
- * \code
+ * \begincode
  * // in file objective_registry.cc
  * DMLC_REGISTRY_ENABLE(MyObjective);
  * DMLC_REGISTRY_LINK_TAG(regression_op);
diff --git a/make/config.mk b/make/config.mk
index a6be9ad..fa8933e 100644
--- a/make/config.mk
+++ b/make/config.mk
@@ -51,3 +51,6 @@ GTEST_PATH=
 
 # path to third-party dependences such as glog
 DEPS_PATH=
+
+# whether to use gnu++11 (Cygwin need this turned on to avoid compile error)
+USE_GNU11=0
diff --git a/scripts/s390x/Dockerfile b/scripts/s390x/Dockerfile
index 5ad4a78..3a52f9d 100644
--- a/scripts/s390x/Dockerfile
+++ b/scripts/s390x/Dockerfile
@@ -1,26 +1,27 @@
-FROM s390x/ubuntu:20.04
+FROM multiarch/debian-debootstrap:s390x-jessie
 
-# Environment
 ENV DEBIAN_FRONTEND noninteractive
-SHELL ["/bin/bash", "-c"]   # Use Bash as shell
-
-# Install all basic requirements
-RUN \
-    apt-get update && \
-    apt-get install -y --no-install-recommends tar unzip wget git build-essential ninja-build \
-      cmake time python3 python3-pip python3-numpy python3-scipy python3-sklearn r-base && \
-    python3 -m pip install pytest hypothesis
-
 ENV GOSU_VERSION 1.10
 
+RUN uname -a
+# Add repositories for Debian Jessie
+RUN printf 'deb http://deb.debian.org/debian/ oldstable main contrib non-free\ndeb-src http://deb.debian.org/debian/ oldstable main contrib non-free\ndeb http://deb.debian.org/debian/ oldstable-updates main contrib non-free\ndeb-src http://deb.debian.org/debian/ oldstable-updates main contrib non-free\ndeb http://deb.debian.org/debian-security oldstable/updates main' > /etc/apt/sources.list
+RUN apt-get update && \
+  apt-get install -y --no-install-suggests --no-install-recommends \
+  build-essential \
+  gcc \
+  make \
+  git \
+  cmake \
+  ca-certificates && \
+  update-ca-certificates --fresh
+
 # Install lightweight sudo (not bound to TTY)
 RUN set -ex; \
-    wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-amd64" && \
+    wget --no-check-certificate -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-amd64" && \
     chmod +x /usr/local/bin/gosu && \
     gosu nobody true
 
-# Default entry-point to use if running locally
-# It will preserve attributes of created files
 COPY entrypoint.sh /scripts/
 
 WORKDIR /workspace
diff --git a/scripts/test_script.sh b/scripts/test_script.sh
index f133bf0..7e0449c 100755
--- a/scripts/test_script.sh
+++ b/scripts/test_script.sh
@@ -4,11 +4,10 @@ set -e
 set -x
 
 if [[ ${TASK} == "lint" ]]; then
-    # Disable pylint for now as they are not yet fixed.
     # stop the build if there are Python syntax errors or undefined names
-    # python3 -m flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
+    python3 -m flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
     # exit-zero treats all errors as warnings.  The GitHub editor is 127 chars wide
-    # python3 -m flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
+    python3 -m flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
 
     make lint
     make doxygen 2>log.txt
@@ -23,8 +22,8 @@ if [[ ${TASK} == "unittest_gtest" ]]; then
     cp make/config.mk .
     if [[ $(uname) != "Darwin" ]]; then
         echo "USE_S3=1" >> config.mk
-        echo "export CXX = g++-5" >> config.mk
-        export CXX=g++-5
+        echo "export CXX = g++-4.8" >> config.mk
+        export CXX=g++-4.8
     else
         echo "USE_S3=0" >> config.mk
         echo "USE_OPENMP=1" >> config.mk
diff --git a/src/io/hdfs_filesys.cc b/src/io/hdfs_filesys.cc
index 09503c4..6d22750 100644
--- a/src/io/hdfs_filesys.cc
+++ b/src/io/hdfs_filesys.cc
@@ -31,8 +31,8 @@ class HDFSStream : public SeekStream {
   virtual size_t Read(void *ptr, size_t size) {
     char *buf = static_cast<char*>(ptr);
     size_t nleft = size;
-    size_t nmax = static_cast<size_t>(std::numeric_limits<tSize>::max());
     while (nleft != 0) {
+      size_t nmax = static_cast<size_t>(std::numeric_limits<tSize>::max());
       tSize ret = hdfsRead(fs_, fp_, buf, std::min(nleft, nmax));
       if (ret > 0) {
         size_t n = static_cast<size_t>(ret);
@@ -50,25 +50,14 @@ class HDFSStream : public SeekStream {
 
   virtual void Write(const void *ptr, size_t size) {
     const char *buf = reinterpret_cast<const char*>(ptr);
-    size_t nleft = size;
-    // When using builtin-java classes to write, the maximum write size
-    // would be limited by the the max array size, which is uncertain
-    // Here I used half of the max limit of tSize(int32_t) as nmax, to avoid
-    // upper bound overflow.
-    // More about max array size:
-    // https://stackoverflow.com/questions/31382531/why-i-cant-create-an-array-with-large-size
-    const size_t nmax = static_cast<size_t>(std::numeric_limits<tSize>::max()) / 2;
-    while (nleft != 0) {
-      tSize ret = hdfsWrite(fs_, fp_, buf, std::min(nleft, nmax));
-      if (ret > 0) {
-        size_t n = static_cast<size_t>(ret);
-        nleft -= n; buf += n;
-      } else if (ret == 0) {
-        break;
-      } else {
+    while (size != 0) {
+      tSize nwrite = hdfsWrite(fs_, fp_, buf, size);
+      if (nwrite == -1) {
         int errsv = errno;
         LOG(FATAL) << "HDFSStream.hdfsWrite Error:" << strerror(errsv);
       }
+      size_t sz = static_cast<size_t>(nwrite);
+      buf += sz; size -= sz;
     }
   }
   virtual void Seek(size_t pos) {
diff --git a/test/unittest/unittest_logging.cc b/test/unittest/unittest_logging.cc
index f8820b5..c0e81d6 100644
--- a/test/unittest/unittest_logging.cc
+++ b/test/unittest/unittest_logging.cc
@@ -1,5 +1,5 @@
 // Copyright by Contributors
-#define DMLC_LOG_FATAL_THROW 1
+#define DMLC_LOG_FATAL_THROW 0
 
 #include <dmlc/logging.h>
 #include <gtest/gtest.h>
@@ -15,44 +15,5 @@ TEST(Logging, basics) {
   int *z = &x;
   CHECK_EQ(*CHECK_NOTNULL(z), x);
 
-  EXPECT_THROW(CHECK_NE(x, y), dmlc::Error);
-}
-
-TEST(Logging, signed_compare) {
-  int32_t x = 1;
-  uint32_t y = 2;
-  CHECK_GT(y, x);
-
-  EXPECT_THROW(CHECK_EQ(x, y), dmlc::Error);
-}
-
-TEST(Logging, expression_in_check) {
-  uint32_t y = 64;
-  CHECK_EQ(y & (y - 1), 0);
-}
-
-TEST(Logging, extra_message) {
-  uint32_t y = 64;
-  CHECK_EQ(y & (y - 1), 0) << y << " has to be power of 2";
-}
-
-TEST(Logging, single_evaluation) {
-  uint32_t y = 1;
-  try {
-    CHECK_EQ(y++, 2);
-    FAIL() << "y = 1; CHECK_EQ(y++, 2) must throw an exception";
-  } catch (std::runtime_error& exception) {
-    // if everything is correct, y++ is evaluated only once, and '1' would be
-    // mentioned in error message. This relies on specific format of error message,
-    // if it changes, this unit test will have to be changed as well.
-    EXPECT_NE(std::string(exception.what()).find("(1 vs"), std::string::npos);
-  } catch (...) {
-    FAIL() << "unexpected exception in CHECK_EQ(y++, 2)"; 
-  }
-}
-
-TEST(Logging, throw_fatal) {
-  EXPECT_THROW({
-    LOG(FATAL) << "message";
-  }, dmlc::Error);
+  ASSERT_DEATH(CHECK_NE(x, y), ".*");
 }
diff --git a/test/unittest/unittest_param.cc b/test/unittest/unittest_param.cc
index 6a94ee9..88450a2 100644
--- a/test/unittest/unittest_param.cc
+++ b/test/unittest/unittest_param.cc
@@ -162,21 +162,28 @@ TEST(Parameter, parsing_float) {
 
 TEST(Parameter, Update) {
   LearningParam param;
+  bool changed = false;
   using Args = std::vector<std::pair<std::string, std::string> >;
   auto unknown =
       param.UpdateAllowUnknown(Args{{"float_param", "0.02"},
-                                    {"foo", "bar"}});
+                                    {"foo", "bar"}}, &changed);
   ASSERT_EQ(unknown.size(), 1);
   ASSERT_EQ(unknown[0].first, "foo");
   ASSERT_EQ(unknown[0].second, "bar");
   ASSERT_NEAR(param.float_param, 0.02f, 1e-6);
+  ASSERT_TRUE(changed);
 
   param.float_param = 0.02;
   param.UpdateAllowUnknown(Args{{"float_param", "0.02"},
-                                {"foo", "bar"}});
-  param.UpdateAllowUnknown(Args{{"foo", "bar"}});
+                                {"foo", "bar"}}, &changed);
+  ASSERT_FALSE(changed);
+
+  param.UpdateAllowUnknown(Args{{"foo", "bar"}}, &changed);
+  ASSERT_FALSE(changed);
+
   param.UpdateAllowUnknown(Args{{"double_param", "0.13"},
-                                {"foo", "bar"}});
+                                {"foo", "bar"}}, &changed);
+  ASSERT_TRUE(changed);
   ASSERT_NEAR(param.float_param, 0.02f, 1e-6);  // stays the same
   ASSERT_NEAR(param.double_param, 0.13, 1e-6);
 }
diff --git a/test/unittest/unittest_thread_group.cc b/test/unittest/unittest_thread_group.cc
index e030951..75186df 100644
--- a/test/unittest/unittest_thread_group.cc
+++ b/test/unittest/unittest_thread_group.cc
@@ -191,7 +191,8 @@ TEST(ThreadGroup, TimerThread) {
       if ((count + 1) % 5 == 0) {
         // output slows it down a bit, so print fewer times
         std::cout << "[" << (count + 1) << "] TIME: "
-                  << GetDurationInMilliseconds(start_time) << "\n";
+                  << GetDurationInMilliseconds(start_time)
+                  << std::endl << std::flush;
       }
       ++count;
       return 0;  // return 0 means continue
@@ -201,8 +202,8 @@ TEST(ThreadGroup, TimerThread) {
   thread_group->request_shutdown_all(true);
   // Wait for all of the queue threads to exit
   thread_group->join_all();
-  GTEST_ASSERT_GE(count, MIN_COUNT_WHILE_SLEEPING);  // Should have at least done 10
-  GTEST_ASSERT_LE(count, MAX_COUNT_WHILE_SLEEPING); // Should not have had time to do 150 of them
+  GTEST_ASSERT_GE(count, MIN_COUNT_WHILE_SLEEPING);  // Should have at least done three
+  GTEST_ASSERT_LE(count, MAX_COUNT_WHILE_SLEEPING); // Should not have had time to do 20 of them
 }
 
 /*!
@@ -223,7 +224,8 @@ TEST(ThreadGroup, TimerThreadSimple) {
                       if ((count + 1) % 5 == 0) {
                         // output slows it down a bit, so print fewer times
                         std::cout << "[" << (count + 1) << "] TIME: "
-                                  << GetDurationInMilliseconds(start_time) << "\n";
+                                  << GetDurationInMilliseconds(start_time)
+                                  << std::endl << std::flush;
                       }
                       ++count;
                       return 0;  // return 0 means continue
@@ -233,6 +235,6 @@ TEST(ThreadGroup, TimerThreadSimple) {
   thread_group->request_shutdown_all();
   // Wait for all of the queue threads to exit
   thread_group->join_all();
-  GTEST_ASSERT_GE(count, MIN_COUNT_WHILE_SLEEPING);  // Should have at least done 10
-  GTEST_ASSERT_LE(count, MAX_COUNT_WHILE_SLEEPING); // Should not have had time to do 150 of them
+  GTEST_ASSERT_GE(count, MIN_COUNT_WHILE_SLEEPING);  // Should have at least done three
+  GTEST_ASSERT_LE(count, MAX_COUNT_WHILE_SLEEPING); // Should not have had time to do 20 of them
 }
