diff --git a/cmake/GetGitRevisionDescription.cmake b/cmake/GetGitRevisionDescription.cmake
index 480a8a9e7..e7f59f978 100644
--- a/cmake/GetGitRevisionDescription.cmake
+++ b/cmake/GetGitRevisionDescription.cmake
@@ -1,33 +1,33 @@
-# * Returns a version string from Git
+# - Returns a version string from Git
 #
-# These functions force a re-configure on each git commit so that you can trust the values of the
-# variables in your build system.
+# These functions force a re-configure on each git commit so that you can
+# trust the values of the variables in your build system.
 #
-# get_git_head_revision(<refspecvar> <hashvar> [<additional arguments to git describe> ...])
+#  get_git_head_revision(<refspecvar> <hashvar> [ALLOW_LOOKING_ABOVE_CMAKE_SOURCE_DIR])
 #
 # Returns the refspec and sha hash of the current head revision
 #
-# git_describe(<var> [<additional arguments to git describe> ...])
+#  git_describe(<var> [<additional arguments to git describe> ...])
 #
-# Returns the results of git describe on the source tree, and adjusting the output so that it tests
-# false if an error occurs.
+# Returns the results of git describe on the source tree, and adjusting
+# the output so that it tests false if an error occurs.
 #
-# git_get_exact_tag(<var> [<additional arguments to git describe> ...])
+#  git_describe_working_tree(<var> [<additional arguments to git describe> ...])
 #
-# Returns the results of git describe --exact-match on the source tree, and adjusting the output so
-# that it tests false if there was no exact matching tag.
+# Returns the results of git describe on the working tree (--dirty option),
+# and adjusting the output so that it tests false if an error occurs.
 #
-# git_local_changes(<var>)
+#  git_get_exact_tag(<var> [<additional arguments to git describe> ...])
 #
-# Returns either "CLEAN" or "DIRTY" with respect to uncommitted changes. Uses the return code of
-# "git diff-index --quiet HEAD --". Does not regard untracked files.
+# Returns the results of git describe --exact-match on the source tree,
+# and adjusting the output so that it tests false if there was no exact
+# matching tag.
 #
-# git_count_parent_commits(<var>)
+#  git_local_changes(<var>)
 #
-# Returns number of commits preceeding current commit -1 if git rev-list --count HEAD failed or
-# "GIT-NOTFOUND" if git executable was not found or "HEAD-HASH-NOTFOUND" if head hash was not found.
-# I don't know if get_git_head_revision() must be called internally or not, as reason of calling it
-# is not clear for me also in git_local_changes().
+# Returns either "CLEAN" or "DIRTY" with respect to uncommitted changes.
+# Uses the return code of "git diff-index --quiet HEAD --".
+# Does not regard untracked files.
 #
 # git_head_commit_timestamp(<var>)
 #
@@ -35,204 +35,256 @@
 #
 # Requires CMake 2.6 or newer (uses the 'function' command)
 #
-# Original Author: 2009-2010 Ryan Pavlik <rpavlik@iastate.edu> <abiryan@ryand.net>
-# http://academic.cleardefinition.com Iowa State University HCI Graduate Program/VRAC
+# Original Author:
+# 2009-2020 Ryan Pavlik <ryan.pavlik@gmail.com> <abiryan@ryand.net>
+# http://academic.cleardefinition.com
 #
-# Copyright Iowa State University 2009-2010. Distributed under the Boost Software License, Version
-# 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+# Copyright 2009-2013, Iowa State University.
+# Copyright 2013-2020, Ryan Pavlik
+# Copyright 2013-2020, Contributors
+# SPDX-License-Identifier: BSL-1.0
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
 
 if(__get_git_revision_description)
-  return()
+    return()
 endif()
 set(__get_git_revision_description YES)
 
-# We must run the following at "include" time, not at function call time, to find the path to this
-# module rather than the path to a calling list file
+# We must run the following at "include" time, not at function call time,
+# to find the path to this module rather than the path to a calling list file
 get_filename_component(_gitdescmoddir ${CMAKE_CURRENT_LIST_FILE} PATH)
 
+# Function _git_find_closest_git_dir finds the next closest .git directory
+# that is part of any directory in the path defined by _start_dir.
+# The result is returned in the parent scope variable whose name is passed
+# as variable _git_dir_var. If no .git directory can be found, the
+# function returns an empty string via _git_dir_var.
+#
+# Example: Given a path C:/bla/foo/bar and assuming C:/bla/.git exists and
+# neither foo nor bar contain a file/directory .git. This wil return
+# C:/bla/.git
+#
+function(_git_find_closest_git_dir _start_dir _git_dir_var)
+    set(cur_dir "${_start_dir}")
+    set(git_dir "${_start_dir}/.git")
+    while(NOT EXISTS "${git_dir}")
+        # .git dir not found, search parent directories
+        set(git_previous_parent "${cur_dir}")
+        get_filename_component(cur_dir "${cur_dir}" DIRECTORY)
+        if(cur_dir STREQUAL git_previous_parent)
+            # We have reached the root directory, we are not in git
+            set(${_git_dir_var}
+                ""
+                PARENT_SCOPE)
+            return()
+        endif()
+        set(git_dir "${cur_dir}/.git")
+    endwhile()
+    set(${_git_dir_var}
+        "${git_dir}"
+        PARENT_SCOPE)
+endfunction()
+
 function(get_git_head_revision _refspecvar _hashvar)
-  set(GIT_PARENT_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
-  set(GIT_DIR "${GIT_PARENT_DIR}/.git")
-  while(NOT EXISTS "${GIT_DIR}") # .git dir not found, search parent directories
-    set(GIT_PREVIOUS_PARENT "${GIT_PARENT_DIR}")
-    get_filename_component(GIT_PARENT_DIR ${GIT_PARENT_DIR} PATH)
-    if(GIT_PARENT_DIR STREQUAL GIT_PREVIOUS_PARENT)
-      # We have reached the root directory, we are not in git
-      set(${_refspecvar}
-          "GITDIR-NOTFOUND"
-          PARENT_SCOPE
-          )
-      set(${_hashvar}
-          "GITDIR-NOTFOUND"
-          PARENT_SCOPE
-          )
-      return()
+    _git_find_closest_git_dir("${CMAKE_CURRENT_SOURCE_DIR}" GIT_DIR)
+
+    if("${ARGN}" STREQUAL "ALLOW_LOOKING_ABOVE_CMAKE_SOURCE_DIR")
+        set(ALLOW_LOOKING_ABOVE_CMAKE_SOURCE_DIR TRUE)
+    else()
+        set(ALLOW_LOOKING_ABOVE_CMAKE_SOURCE_DIR FALSE)
+    endif()
+    if(NOT "${GIT_DIR}" STREQUAL "")
+        file(RELATIVE_PATH _relative_to_source_dir "${CMAKE_SOURCE_DIR}"
+             "${GIT_DIR}")
+        if("${_relative_to_source_dir}" MATCHES "[.][.]" AND NOT ALLOW_LOOKING_ABOVE_CMAKE_SOURCE_DIR)
+            # We've gone above the CMake root dir.
+            set(GIT_DIR "")
+        endif()
+    endif()
+    if("${GIT_DIR}" STREQUAL "")
+        set(${_refspecvar}
+            "GITDIR-NOTFOUND"
+            PARENT_SCOPE)
+        set(${_hashvar}
+            "GITDIR-NOTFOUND"
+            PARENT_SCOPE)
+        return()
     endif()
-    set(GIT_DIR "${GIT_PARENT_DIR}/.git")
-  endwhile()
-  # check if this is a submodule
-  if(NOT IS_DIRECTORY ${GIT_DIR})
-    file(READ ${GIT_DIR} submodule)
-    string(REGEX REPLACE "gitdir: (.*)\n$" "\\1" GIT_DIR_RELATIVE ${submodule})
-    get_filename_component(SUBMODULE_DIR ${GIT_DIR} PATH)
-    get_filename_component(GIT_DIR ${SUBMODULE_DIR}/${GIT_DIR_RELATIVE} ABSOLUTE)
-  endif()
-  set(GIT_DATA "${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/git-data")
-  if(NOT EXISTS "${GIT_DATA}")
-    file(MAKE_DIRECTORY "${GIT_DATA}")
-  endif()
 
-  if(NOT EXISTS "${GIT_DIR}/HEAD")
-    return()
-  endif()
-  set(HEAD_FILE "${GIT_DATA}/HEAD")
-  configure_file("${GIT_DIR}/HEAD" "${HEAD_FILE}" COPYONLY)
+    # Check if the current source dir is a git submodule or a worktree.
+    # In both cases .git is a file instead of a directory.
+    #
+    if(NOT IS_DIRECTORY ${GIT_DIR})
+        # The following git command will return a non empty string that
+        # points to the super project working tree if the current
+        # source dir is inside a git submodule.
+        # Otherwise the command will return an empty string.
+        #
+        execute_process(
+            COMMAND "${GIT_EXECUTABLE}" rev-parse
+                    --show-superproject-working-tree
+            WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+            OUTPUT_VARIABLE out
+            ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
+        if(NOT "${out}" STREQUAL "")
+            # If out is empty, GIT_DIR/CMAKE_CURRENT_SOURCE_DIR is in a submodule
+            file(READ ${GIT_DIR} submodule)
+            string(REGEX REPLACE "gitdir: (.*)$" "\\1" GIT_DIR_RELATIVE
+                                 ${submodule})
+            string(STRIP ${GIT_DIR_RELATIVE} GIT_DIR_RELATIVE)
+            get_filename_component(SUBMODULE_DIR ${GIT_DIR} PATH)
+            get_filename_component(GIT_DIR ${SUBMODULE_DIR}/${GIT_DIR_RELATIVE}
+                                   ABSOLUTE)
+            set(HEAD_SOURCE_FILE "${GIT_DIR}/HEAD")
+        else()
+            # GIT_DIR/CMAKE_CURRENT_SOURCE_DIR is in a worktree
+            file(READ ${GIT_DIR} worktree_ref)
+            # The .git directory contains a path to the worktree information directory
+            # inside the parent git repo of the worktree.
+            #
+            string(REGEX REPLACE "gitdir: (.*)$" "\\1" git_worktree_dir
+                                 ${worktree_ref})
+            string(STRIP ${git_worktree_dir} git_worktree_dir)
+            _git_find_closest_git_dir("${git_worktree_dir}" GIT_DIR)
+            set(HEAD_SOURCE_FILE "${git_worktree_dir}/HEAD")
+        endif()
+    else()
+        set(HEAD_SOURCE_FILE "${GIT_DIR}/HEAD")
+    endif()
+    set(GIT_DATA "${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/git-data")
+    if(NOT EXISTS "${GIT_DATA}")
+        file(MAKE_DIRECTORY "${GIT_DATA}")
+    endif()
 
-  configure_file(
-    "${_gitdescmoddir}/GetGitRevisionDescription.cmake.in" "${GIT_DATA}/grabRef.cmake" @ONLY
-    )
-  include("${GIT_DATA}/grabRef.cmake")
+    if(NOT EXISTS "${HEAD_SOURCE_FILE}")
+        return()
+    endif()
+    set(HEAD_FILE "${GIT_DATA}/HEAD")
+    configure_file("${HEAD_SOURCE_FILE}" "${HEAD_FILE}" COPYONLY)
 
-  set(${_refspecvar}
-      "${HEAD_REF}"
-      PARENT_SCOPE
-      )
-  set(${_hashvar}
-      "${HEAD_HASH}"
-      PARENT_SCOPE
-      )
+    configure_file("${_gitdescmoddir}/GetGitRevisionDescription.cmake.in"
+                   "${GIT_DATA}/grabRef.cmake" @ONLY)
+    include("${GIT_DATA}/grabRef.cmake")
+
+    set(${_refspecvar}
+        "${HEAD_REF}"
+        PARENT_SCOPE)
+    set(${_hashvar}
+        "${HEAD_HASH}"
+        PARENT_SCOPE)
 endfunction()
 
 function(git_describe _var)
-  if(NOT GIT_FOUND)
-    find_package(Git QUIET)
-  endif()
-  get_git_head_revision(refspec hash)
-  if(NOT GIT_FOUND)
+    if(NOT GIT_FOUND)
+        find_package(Git QUIET)
+    endif()
+    get_git_head_revision(refspec hash)
+    if(NOT GIT_FOUND)
+        set(${_var}
+            "GIT-NOTFOUND"
+            PARENT_SCOPE)
+        return()
+    endif()
+    if(NOT hash)
+        set(${_var}
+            "HEAD-HASH-NOTFOUND"
+            PARENT_SCOPE)
+        return()
+    endif()
+
+    # TODO sanitize
+    #if((${ARGN}" MATCHES "&&") OR
+    #	(ARGN MATCHES "||") OR
+    #	(ARGN MATCHES "\\;"))
+    #	message("Please report the following error to the project!")
+    #	message(FATAL_ERROR "Looks like someone's doing something nefarious with git_describe! Passed arguments ${ARGN}")
+    #endif()
+
+    #message(STATUS "Arguments to execute_process: ${ARGN}")
+
+    execute_process(
+        COMMAND "${GIT_EXECUTABLE}" describe --tags --always ${hash} ${ARGN}
+        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        RESULT_VARIABLE res
+        OUTPUT_VARIABLE out
+        ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
+    if(NOT res EQUAL 0)
+        set(out "${out}-${res}-NOTFOUND")
+    endif()
+
     set(${_var}
-        "GIT-NOTFOUND"
-        PARENT_SCOPE
-        )
-    return()
-  endif()
-  if(NOT hash)
+        "${out}"
+        PARENT_SCOPE)
+endfunction()
+
+function(git_describe_working_tree _var)
+    if(NOT GIT_FOUND)
+        find_package(Git QUIET)
+    endif()
+    if(NOT GIT_FOUND)
+        set(${_var}
+            "GIT-NOTFOUND"
+            PARENT_SCOPE)
+        return()
+    endif()
+
+    execute_process(
+        COMMAND "${GIT_EXECUTABLE}" describe --dirty ${ARGN}
+        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        RESULT_VARIABLE res
+        OUTPUT_VARIABLE out
+        ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
+    if(NOT res EQUAL 0)
+        set(out "${out}-${res}-NOTFOUND")
+    endif()
+
     set(${_var}
-        "HEAD-HASH-NOTFOUND"
-        PARENT_SCOPE
-        )
-    return()
-  endif()
-
-  # TODO sanitize if((${ARGN}" MATCHES "&&") OR (ARGN MATCHES "||") OR (ARGN MATCHES "\\;"))
-  # message("Please report the following error to the project!") message(FATAL_ERROR "Looks like
-  # someone's doing something nefarious with git_describe! Passed arguments ${ARGN}") endif()
-
-  # message(STATUS "Arguments to execute_process: ${ARGN}")
-
-  execute_process(
-    COMMAND "${GIT_EXECUTABLE}" describe ${hash} ${ARGN}
-    WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
-    RESULT_VARIABLE res
-    OUTPUT_VARIABLE out
-    ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE
-    )
-  if(NOT res EQUAL 0)
-    set(out "${out}-${res}-NOTFOUND")
-  endif()
-
-  set(${_var}
-      "${out}"
-      PARENT_SCOPE
-      )
+        "${out}"
+        PARENT_SCOPE)
 endfunction()
 
 function(git_get_exact_tag _var)
-  git_describe(out --exact-match ${ARGN})
-  set(${_var}
-      "${out}"
-      PARENT_SCOPE
-      )
+    git_describe(out --exact-match ${ARGN})
+    set(${_var}
+        "${out}"
+        PARENT_SCOPE)
 endfunction()
 
 function(git_local_changes _var)
-  if(NOT GIT_FOUND)
-    find_package(Git QUIET)
-  endif()
-  get_git_head_revision(refspec hash)
-  if(NOT GIT_FOUND)
-    set(${_var}
-        "GIT-NOTFOUND"
-        PARENT_SCOPE
-        )
-    return()
-  endif()
-  if(NOT hash)
-    set(${_var}
-        "HEAD-HASH-NOTFOUND"
-        PARENT_SCOPE
-        )
-    return()
-  endif()
-
-  execute_process(
-    COMMAND "${GIT_EXECUTABLE}" diff-index --quiet HEAD --
-    WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
-    RESULT_VARIABLE res
-    OUTPUT_VARIABLE out
-    ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE
-    )
-  if(res EQUAL 0)
-    set(${_var}
-        "CLEAN"
-        PARENT_SCOPE
-        )
-  else()
-    set(${_var}
-        "DIRTY"
-        PARENT_SCOPE
-        )
-  endif()
-endfunction()
-
-function(git_count_parent_commits _var)
-  if(NOT GIT_FOUND)
-    find_package(Git QUIET)
-  endif()
-  get_git_head_revision(refspec hash)
-  if(NOT GIT_FOUND)
-    set(${_var}
-        "GIT-NOTFOUND"
-        PARENT_SCOPE
-        )
-    return()
-  endif()
-  if(NOT hash)
-    set(${_var}
-        "HEAD-HASH-NOTFOUND"
-        PARENT_SCOPE
-        )
-    return()
-  endif()
-
-  execute_process(
-    COMMAND "${GIT_EXECUTABLE}" rev-list --count HEAD
-    WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
-    RESULT_VARIABLE res
-    OUTPUT_VARIABLE out
-    ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE
-    )
-  if(res EQUAL 0)
-    set(${_var}
-        "${out}"
-        PARENT_SCOPE
-        )
-  else()
-    set(${_var}
-        "-1"
-        PARENT_SCOPE
-        )
-  endif()
+    if(NOT GIT_FOUND)
+        find_package(Git QUIET)
+    endif()
+    get_git_head_revision(refspec hash)
+    if(NOT GIT_FOUND)
+        set(${_var}
+            "GIT-NOTFOUND"
+            PARENT_SCOPE)
+        return()
+    endif()
+    if(NOT hash)
+        set(${_var}
+            "HEAD-HASH-NOTFOUND"
+            PARENT_SCOPE)
+        return()
+    endif()
 
+    execute_process(
+        COMMAND "${GIT_EXECUTABLE}" diff-index --quiet HEAD --
+        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        RESULT_VARIABLE res
+        OUTPUT_VARIABLE out
+        ERROR_QUIET OUTPUT_STRIP_TRAILING_WHITESPACE)
+    if(res EQUAL 0)
+        set(${_var}
+            "CLEAN"
+            PARENT_SCOPE)
+    else()
+        set(${_var}
+            "DIRTY"
+            PARENT_SCOPE)
+    endif()
 endfunction()
 
 function(git_get_commit_timestamp _var hash)
diff --git a/cmake/GetGitRevisionDescription.cmake.in b/cmake/GetGitRevisionDescription.cmake.in
index f7d93ddf8..116efc4e4 100644
--- a/cmake/GetGitRevisionDescription.cmake.in
+++ b/cmake/GetGitRevisionDescription.cmake.in
@@ -3,11 +3,17 @@
 #
 # Requires CMake 2.6 or newer (uses the 'function' command)
 #
-# Original Author: 2009-2010 Ryan Pavlik <rpavlik@iastate.edu> <abiryan@ryand.net>
-# http://academic.cleardefinition.com Iowa State University HCI Graduate Program/VRAC
+# Original Author:
+# 2009-2010 Ryan Pavlik <rpavlik@iastate.edu> <abiryan@ryand.net>
+# http://academic.cleardefinition.com
+# Iowa State University HCI Graduate Program/VRAC
 #
-# Copyright Iowa State University 2009-2010. Distributed under the Boost Software License, Version
-# 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+# Copyright 2009-2012, Iowa State University
+# Copyright 2011-2015, Contributors
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
+# SPDX-License-Identifier: BSL-1.0
 
 set(HEAD_HASH)
 
@@ -15,23 +21,23 @@ file(READ "@HEAD_FILE@" HEAD_CONTENTS LIMIT 1024)
 
 string(STRIP "${HEAD_CONTENTS}" HEAD_CONTENTS)
 if(HEAD_CONTENTS MATCHES "ref")
-  # named branch
-  string(REPLACE "ref: " "" HEAD_REF "${HEAD_CONTENTS}")
-  if(EXISTS "@GIT_DIR@/${HEAD_REF}")
-    configure_file("@GIT_DIR@/${HEAD_REF}" "@GIT_DATA@/head-ref" COPYONLY)
-  else()
-    configure_file("@GIT_DIR@/packed-refs" "@GIT_DATA@/packed-refs" COPYONLY)
-    file(READ "@GIT_DATA@/packed-refs" PACKED_REFS)
-    if(${PACKED_REFS} MATCHES "([0-9a-z]*) ${HEAD_REF}")
-      set(HEAD_HASH "${CMAKE_MATCH_1}")
-    endif()
-  endif()
+	# named branch
+	string(REPLACE "ref: " "" HEAD_REF "${HEAD_CONTENTS}")
+	if(EXISTS "@GIT_DIR@/${HEAD_REF}")
+		configure_file("@GIT_DIR@/${HEAD_REF}" "@GIT_DATA@/head-ref" COPYONLY)
+	else()
+		configure_file("@GIT_DIR@/packed-refs" "@GIT_DATA@/packed-refs" COPYONLY)
+		file(READ "@GIT_DATA@/packed-refs" PACKED_REFS)
+		if(${PACKED_REFS} MATCHES "([0-9a-z]*) ${HEAD_REF}")
+			set(HEAD_HASH "${CMAKE_MATCH_1}")
+		endif()
+	endif()
 else()
-  # detached HEAD
-  configure_file("@GIT_DIR@/HEAD" "@GIT_DATA@/head-ref" COPYONLY)
+	# detached HEAD
+	configure_file("@GIT_DIR@/HEAD" "@GIT_DATA@/head-ref" COPYONLY)
 endif()
 
 if(NOT HEAD_HASH)
-  file(READ "@GIT_DATA@/head-ref" HEAD_HASH LIMIT 1024)
-  string(STRIP "${HEAD_HASH}" HEAD_HASH)
+	file(READ "@GIT_DATA@/head-ref" HEAD_HASH LIMIT 1024)
+	string(STRIP "${HEAD_HASH}" HEAD_HASH)
 endif()