diff --git a/config/depcomp b/config/depcomp
index df8eea7e..715e3431 100755
--- a/config/depcomp
+++ b/config/depcomp
@@ -1,10 +1,9 @@
 #! /bin/sh
 # depcomp - compile a program generating dependencies as side-effects
 
-scriptversion=2009-04-28.21; # UTC
+scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1999, 2000, 2003, 2004, 2005, 2006, 2007, 2009 Free
-# Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -17,7 +16,7 @@ scriptversion=2009-04-28.21; # UTC
 # GNU General Public License for more details.
 
 # You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 # As a special exception to the GNU General Public License, if you
 # distribute this file as part of a program that contains a
@@ -28,9 +27,9 @@ scriptversion=2009-04-28.21; # UTC
 
 case $1 in
   '')
-     echo "$0: No command.  Try \`$0 --help' for more information." 1>&2
-     exit 1;
-     ;;
+    echo "$0: No command.  Try '$0 --help' for more information." 1>&2
+    exit 1;
+    ;;
   -h | --h*)
     cat <<\EOF
 Usage: depcomp [--help] [--version] PROGRAM [ARGS]
@@ -40,11 +39,11 @@ as side-effects.
 
 Environment variables:
   depmode     Dependency tracking mode.
-  source      Source file read by `PROGRAMS ARGS'.
-  object      Object file output by `PROGRAMS ARGS'.
+  source      Source file read by 'PROGRAMS ARGS'.
+  object      Object file output by 'PROGRAMS ARGS'.
   DEPDIR      directory where to store dependencies.
   depfile     Dependency file to output.
-  tmpdepfile  Temporary file to use when outputing dependencies.
+  tmpdepfile  Temporary file to use when outputting dependencies.
   libtool     Whether libtool is used (yes/no).
 
 Report bugs to <bug-automake@gnu.org>.
@@ -57,6 +56,66 @@ EOF
     ;;
 esac
 
+# Get the directory component of the given path, and save it in the
+# global variables '$dir'.  Note that this directory component will
+# be either empty or ending with a '/' character.  This is deliberate.
+set_dir_from ()
+{
+  case $1 in
+    */*) dir=`echo "$1" | sed -e 's|/[^/]*$|/|'`;;
+      *) dir=;;
+  esac
+}
+
+# Get the suffix-stripped basename of the given path, and save it the
+# global variable '$base'.
+set_base_from ()
+{
+  base=`echo "$1" | sed -e 's|^.*/||' -e 's/\.[^.]*$//'`
+}
+
+# If no dependency file was actually created by the compiler invocation,
+# we still have to create a dummy depfile, to avoid errors with the
+# Makefile "include basename.Plo" scheme.
+make_dummy_depfile ()
+{
+  echo "#dummy" > "$depfile"
+}
+
+# Factor out some common post-processing of the generated depfile.
+# Requires the auxiliary global variable '$tmpdepfile' to be set.
+aix_post_process_depfile ()
+{
+  # If the compiler actually managed to produce a dependency file,
+  # post-process it.
+  if test -f "$tmpdepfile"; then
+    # Each line is of the form 'foo.o: dependency.h'.
+    # Do two passes, one to just change these to
+    #   $object: dependency.h
+    # and one to simply output
+    #   dependency.h:
+    # which is needed to avoid the deleted-header problem.
+    { sed -e "s,^.*\.[$lower]*:,$object:," < "$tmpdepfile"
+      sed -e "s,^.*\.[$lower]*:[$tab ]*,," -e 's,$,:,' < "$tmpdepfile"
+    } > "$depfile"
+    rm -f "$tmpdepfile"
+  else
+    make_dummy_depfile
+  fi
+}
+
+# A tabulation character.
+tab='	'
+# A newline character.
+nl='
+'
+# Character ranges might be problematic outside the C locale.
+# These definitions help.
+upper=ABCDEFGHIJKLMNOPQRSTUVWXYZ
+lower=abcdefghijklmnopqrstuvwxyz
+digits=0123456789
+alpha=${upper}${lower}
+
 if test -z "$depmode" || test -z "$source" || test -z "$object"; then
   echo "depcomp: Variables source, object and depmode must be set" 1>&2
   exit 1
@@ -69,6 +128,9 @@ tmpdepfile=${tmpdepfile-`echo "$depfile" | sed 's/\.\([^.]*\)$/.T\1/'`}
 
 rm -f "$tmpdepfile"
 
+# Avoid interferences from the environment.
+gccflag= dashmflag=
+
 # Some modes work just like other modes, but use different flags.  We
 # parameterize here, but still list the modes in the big case below,
 # to make depend.m4 easier to write.  Note that we *cannot* use a case
@@ -80,18 +142,32 @@ if test "$depmode" = hp; then
 fi
 
 if test "$depmode" = dashXmstdout; then
-   # This is just like dashmstdout with a different argument.
-   dashmflag=-xM
-   depmode=dashmstdout
+  # This is just like dashmstdout with a different argument.
+  dashmflag=-xM
+  depmode=dashmstdout
 fi
 
 cygpath_u="cygpath -u -f -"
 if test "$depmode" = msvcmsys; then
-   # This is just like msvisualcpp but w/o cygpath translation.
-   # Just convert the backslash-escaped backslashes to single forward
-   # slashes to satisfy depend.m4
-   cygpath_u="sed s,\\\\\\\\,/,g"
-   depmode=msvisualcpp
+  # This is just like msvisualcpp but w/o cygpath translation.
+  # Just convert the backslash-escaped backslashes to single forward
+  # slashes to satisfy depend.m4
+  cygpath_u='sed s,\\\\,/,g'
+  depmode=msvisualcpp
+fi
+
+if test "$depmode" = msvc7msys; then
+  # This is just like msvc7 but w/o cygpath translation.
+  # Just convert the backslash-escaped backslashes to single forward
+  # slashes to satisfy depend.m4
+  cygpath_u='sed s,\\\\,/,g'
+  depmode=msvc7
+fi
+
+if test "$depmode" = xlc; then
+  # IBM C/C++ Compilers xlc/xlC can output gcc-like dependency information.
+  gccflag=-qmakedep=gcc,-MF
+  depmode=gcc
 fi
 
 case "$depmode" in
@@ -114,8 +190,7 @@ gcc3)
   done
   "$@"
   stat=$?
-  if test $stat -eq 0; then :
-  else
+  if test $stat -ne 0; then
     rm -f "$tmpdepfile"
     exit $stat
   fi
@@ -123,13 +198,17 @@ gcc3)
   ;;
 
 gcc)
+## Note that this doesn't just cater to obsosete pre-3.x GCC compilers.
+## but also to in-use compilers like IMB xlc/xlC and the HP C compiler.
+## (see the conditional assignment to $gccflag above).
 ## There are various ways to get dependency output from gcc.  Here's
 ## why we pick this rather obscure method:
 ## - Don't want to use -MD because we'd like the dependencies to end
 ##   up in a subdir.  Having to rename by hand is ugly.
 ##   (We might end up doing this anyway to support other compilers.)
 ## - The DEPENDENCIES_OUTPUT environment variable makes gcc act like
-##   -MM, not -M (despite what the docs say).
+##   -MM, not -M (despite what the docs say).  Also, it might not be
+##   supported by the other compilers which use the 'gcc' depmode.
 ## - Using -M directly means running the compiler twice (even worse
 ##   than renaming).
   if test -z "$gccflag"; then
@@ -137,31 +216,31 @@ gcc)
   fi
   "$@" -Wp,"$gccflag$tmpdepfile"
   stat=$?
-  if test $stat -eq 0; then :
-  else
+  if test $stat -ne 0; then
     rm -f "$tmpdepfile"
     exit $stat
   fi
   rm -f "$depfile"
   echo "$object : \\" > "$depfile"
-  alpha=ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz
-## The second -e expression handles DOS-style file names with drive letters.
+  # The second -e expression handles DOS-style file names with drive
+  # letters.
   sed -e 's/^[^:]*: / /' \
       -e 's/^['$alpha']:\/[^:]*: / /' < "$tmpdepfile" >> "$depfile"
-## This next piece of magic avoids the `deleted header file' problem.
+## This next piece of magic avoids the "deleted header file" problem.
 ## The problem is that when a header file which appears in a .P file
 ## is deleted, the dependency causes make to die (because there is
 ## typically no way to rebuild the header).  We avoid this by adding
 ## dummy dependencies for each header file.  Too bad gcc doesn't do
 ## this for us directly.
-  tr ' ' '
-' < "$tmpdepfile" |
-## Some versions of gcc put a space before the `:'.  On the theory
+## Some versions of gcc put a space before the ':'.  On the theory
 ## that the space means something, we add a space to the output as
-## well.
+## well.  hp depmode also adds that space, but also prefixes the VPATH
+## to the object.  Take care to not repeat it in the output.
 ## Some versions of the HPUX 10.20 sed can't process this invocation
 ## correctly.  Breaking it into two sed invocations is a workaround.
-    sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' | sed -e 's/$/ :/' >> "$depfile"
+  tr ' ' "$nl" < "$tmpdepfile" \
+    | sed -e 's/^\\$//' -e '/^$/d' -e "s|.*$object$||" -e '/:$/d' \
+    | sed -e 's/$/ :/' >> "$depfile"
   rm -f "$tmpdepfile"
   ;;
 
@@ -179,8 +258,7 @@ sgi)
     "$@" -MDupdate "$tmpdepfile"
   fi
   stat=$?
-  if test $stat -eq 0; then :
-  else
+  if test $stat -ne 0; then
     rm -f "$tmpdepfile"
     exit $stat
   fi
@@ -188,43 +266,41 @@ sgi)
 
   if test -f "$tmpdepfile"; then  # yes, the sourcefile depend on other files
     echo "$object : \\" > "$depfile"
-
     # Clip off the initial element (the dependent).  Don't try to be
     # clever and replace this with sed code, as IRIX sed won't handle
     # lines with more than a fixed number of characters (4096 in
     # IRIX 6.2 sed, 8192 in IRIX 6.5).  We also remove comment lines;
-    # the IRIX cc adds comments like `#:fec' to the end of the
+    # the IRIX cc adds comments like '#:fec' to the end of the
     # dependency line.
-    tr ' ' '
-' < "$tmpdepfile" \
-    | sed -e 's/^.*\.o://' -e 's/#.*$//' -e '/^$/ d' | \
-    tr '
-' ' ' >> "$depfile"
+    tr ' ' "$nl" < "$tmpdepfile" \
+      | sed -e 's/^.*\.o://' -e 's/#.*$//' -e '/^$/ d' \
+      | tr "$nl" ' ' >> "$depfile"
     echo >> "$depfile"
-
     # The second pass generates a dummy entry for each header file.
-    tr ' ' '
-' < "$tmpdepfile" \
-   | sed -e 's/^.*\.o://' -e 's/#.*$//' -e '/^$/ d' -e 's/$/:/' \
-   >> "$depfile"
+    tr ' ' "$nl" < "$tmpdepfile" \
+      | sed -e 's/^.*\.o://' -e 's/#.*$//' -e '/^$/ d' -e 's/$/:/' \
+      >> "$depfile"
   else
-    # The sourcefile does not contain any dependencies, so just
-    # store a dummy comment line, to avoid errors with the Makefile
-    # "include basename.Plo" scheme.
-    echo "#dummy" > "$depfile"
+    make_dummy_depfile
   fi
   rm -f "$tmpdepfile"
   ;;
 
+xlc)
+  # This case exists only to let depend.m4 do its work.  It works by
+  # looking at the text of this script.  This case will never be run,
+  # since it is checked for above.
+  exit 1
+  ;;
+
 aix)
   # The C for AIX Compiler uses -M and outputs the dependencies
   # in a .u file.  In older versions, this file always lives in the
-  # current directory.  Also, the AIX compiler puts `$object:' at the
+  # current directory.  Also, the AIX compiler puts '$object:' at the
   # start of each line; $object doesn't have directory information.
   # Version 6 uses the directory in both cases.
-  dir=`echo "$object" | sed -e 's|/[^/]*$|/|'`
-  test "x$dir" = "x$object" && dir=
-  base=`echo "$object" | sed -e 's|^.*/||' -e 's/\.o$//' -e 's/\.lo$//'`
+  set_dir_from "$object"
+  set_base_from "$object"
   if test "$libtool" = yes; then
     tmpdepfile1=$dir$base.u
     tmpdepfile2=$base.u
@@ -237,9 +313,7 @@ aix)
     "$@" -M
   fi
   stat=$?
-
-  if test $stat -eq 0; then :
-  else
+  if test $stat -ne 0; then
     rm -f "$tmpdepfile1" "$tmpdepfile2" "$tmpdepfile3"
     exit $stat
   fi
@@ -248,44 +322,100 @@ aix)
   do
     test -f "$tmpdepfile" && break
   done
-  if test -f "$tmpdepfile"; then
-    # Each line is of the form `foo.o: dependent.h'.
-    # Do two passes, one to just change these to
-    # `$object: dependent.h' and one to simply `dependent.h:'.
-    sed -e "s,^.*\.[a-z]*:,$object:," < "$tmpdepfile" > "$depfile"
-    # That's a tab and a space in the [].
-    sed -e 's,^.*\.[a-z]*:[	 ]*,,' -e 's,$,:,' < "$tmpdepfile" >> "$depfile"
-  else
-    # The sourcefile does not contain any dependencies, so just
-    # store a dummy comment line, to avoid errors with the Makefile
-    # "include basename.Plo" scheme.
-    echo "#dummy" > "$depfile"
+  aix_post_process_depfile
+  ;;
+
+tcc)
+  # tcc (Tiny C Compiler) understand '-MD -MF file' since version 0.9.26
+  # FIXME: That version still under development at the moment of writing.
+  #        Make that this statement remains true also for stable, released
+  #        versions.
+  # It will wrap lines (doesn't matter whether long or short) with a
+  # trailing '\', as in:
+  #
+  #   foo.o : \
+  #    foo.c \
+  #    foo.h \
+  #
+  # It will put a trailing '\' even on the last line, and will use leading
+  # spaces rather than leading tabs (at least since its commit 0394caf7
+  # "Emit spaces for -MD").
+  "$@" -MD -MF "$tmpdepfile"
+  stat=$?
+  if test $stat -ne 0; then
+    rm -f "$tmpdepfile"
+    exit $stat
   fi
+  rm -f "$depfile"
+  # Each non-empty line is of the form 'foo.o : \' or ' dep.h \'.
+  # We have to change lines of the first kind to '$object: \'.
+  sed -e "s|.*:|$object :|" < "$tmpdepfile" > "$depfile"
+  # And for each line of the second kind, we have to emit a 'dep.h:'
+  # dummy dependency, to avoid the deleted-header problem.
+  sed -n -e 's|^  *\(.*\) *\\$|\1:|p' < "$tmpdepfile" >> "$depfile"
   rm -f "$tmpdepfile"
   ;;
 
-icc)
-  # Intel's C compiler understands `-MD -MF file'.  However on
-  #    icc -MD -MF foo.d -c -o sub/foo.o sub/foo.c
-  # ICC 7.0 will fill foo.d with something like
-  #    foo.o: sub/foo.c
-  #    foo.o: sub/foo.h
-  # which is wrong.  We want:
-  #    sub/foo.o: sub/foo.c
-  #    sub/foo.o: sub/foo.h
-  #    sub/foo.c:
-  #    sub/foo.h:
-  # ICC 7.1 will output
+## The order of this option in the case statement is important, since the
+## shell code in configure will try each of these formats in the order
+## listed in this file.  A plain '-MD' option would be understood by many
+## compilers, so we must ensure this comes after the gcc and icc options.
+pgcc)
+  # Portland's C compiler understands '-MD'.
+  # Will always output deps to 'file.d' where file is the root name of the
+  # source file under compilation, even if file resides in a subdirectory.
+  # The object file name does not affect the name of the '.d' file.
+  # pgcc 10.2 will output
   #    foo.o: sub/foo.c sub/foo.h
-  # and will wrap long lines using \ :
+  # and will wrap long lines using '\' :
   #    foo.o: sub/foo.c ... \
   #     sub/foo.h ... \
   #     ...
+  set_dir_from "$object"
+  # Use the source, not the object, to determine the base name, since
+  # that's sadly what pgcc will do too.
+  set_base_from "$source"
+  tmpdepfile=$base.d
+
+  # For projects that build the same source file twice into different object
+  # files, the pgcc approach of using the *source* file root name can cause
+  # problems in parallel builds.  Use a locking strategy to avoid stomping on
+  # the same $tmpdepfile.
+  lockdir=$base.d-lock
+  trap "
+    echo '$0: caught signal, cleaning up...' >&2
+    rmdir '$lockdir'
+    exit 1
+  " 1 2 13 15
+  numtries=100
+  i=$numtries
+  while test $i -gt 0; do
+    # mkdir is a portable test-and-set.
+    if mkdir "$lockdir" 2>/dev/null; then
+      # This process acquired the lock.
+      "$@" -MD
+      stat=$?
+      # Release the lock.
+      rmdir "$lockdir"
+      break
+    else
+      # If the lock is being held by a different process, wait
+      # until the winning process is done or we timeout.
+      while test -d "$lockdir" && test $i -gt 0; do
+        sleep 1
+        i=`expr $i - 1`
+      done
+    fi
+    i=`expr $i - 1`
+  done
+  trap - 1 2 13 15
+  if test $i -le 0; then
+    echo "$0: failed to acquire lock after $numtries attempts" >&2
+    echo "$0: check lockdir '$lockdir'" >&2
+    exit 1
+  fi
 
-  "$@" -MD -MF "$tmpdepfile"
-  stat=$?
-  if test $stat -eq 0; then :
-  else
+  if test $stat -ne 0; then
     rm -f "$tmpdepfile"
     exit $stat
   fi
@@ -297,8 +427,8 @@ icc)
   sed "s,^[^:]*:,$object :," < "$tmpdepfile" > "$depfile"
   # Some versions of the HPUX 10.20 sed can't process this invocation
   # correctly.  Breaking it into two sed invocations is a workaround.
-  sed 's,^[^:]*: \(.*\)$,\1,;s/^\\$//;/^$/d;/:$/d' < "$tmpdepfile" |
-    sed -e 's/$/ :/' >> "$depfile"
+  sed 's,^[^:]*: \(.*\)$,\1,;s/^\\$//;/^$/d;/:$/d' < "$tmpdepfile" \
+    | sed -e 's/$/ :/' >> "$depfile"
   rm -f "$tmpdepfile"
   ;;
 
@@ -309,9 +439,8 @@ hp2)
   # 'foo.d', which lands next to the object file, wherever that
   # happens to be.
   # Much of this is similar to the tru64 case; see comments there.
-  dir=`echo "$object" | sed -e 's|/[^/]*$|/|'`
-  test "x$dir" = "x$object" && dir=
-  base=`echo "$object" | sed -e 's|^.*/||' -e 's/\.o$//' -e 's/\.lo$//'`
+  set_dir_from  "$object"
+  set_base_from "$object"
   if test "$libtool" = yes; then
     tmpdepfile1=$dir$base.d
     tmpdepfile2=$dir.libs/$base.d
@@ -322,8 +451,7 @@ hp2)
     "$@" +Maked
   fi
   stat=$?
-  if test $stat -eq 0; then :
-  else
+  if test $stat -ne 0; then
      rm -f "$tmpdepfile1" "$tmpdepfile2"
      exit $stat
   fi
@@ -333,77 +461,107 @@ hp2)
     test -f "$tmpdepfile" && break
   done
   if test -f "$tmpdepfile"; then
-    sed -e "s,^.*\.[a-z]*:,$object:," "$tmpdepfile" > "$depfile"
-    # Add `dependent.h:' lines.
+    sed -e "s,^.*\.[$lower]*:,$object:," "$tmpdepfile" > "$depfile"
+    # Add 'dependent.h:' lines.
     sed -ne '2,${
-	       s/^ *//
-	       s/ \\*$//
-	       s/$/:/
-	       p
-	     }' "$tmpdepfile" >> "$depfile"
+               s/^ *//
+               s/ \\*$//
+               s/$/:/
+               p
+             }' "$tmpdepfile" >> "$depfile"
   else
-    echo "#dummy" > "$depfile"
+    make_dummy_depfile
   fi
   rm -f "$tmpdepfile" "$tmpdepfile2"
   ;;
 
 tru64)
-   # The Tru64 compiler uses -MD to generate dependencies as a side
-   # effect.  `cc -MD -o foo.o ...' puts the dependencies into `foo.o.d'.
-   # At least on Alpha/Redhat 6.1, Compaq CCC V6.2-504 seems to put
-   # dependencies in `foo.d' instead, so we check for that too.
-   # Subdirectories are respected.
-   dir=`echo "$object" | sed -e 's|/[^/]*$|/|'`
-   test "x$dir" = "x$object" && dir=
-   base=`echo "$object" | sed -e 's|^.*/||' -e 's/\.o$//' -e 's/\.lo$//'`
-
-   if test "$libtool" = yes; then
-      # With Tru64 cc, shared objects can also be used to make a
-      # static library.  This mechanism is used in libtool 1.4 series to
-      # handle both shared and static libraries in a single compilation.
-      # With libtool 1.4, dependencies were output in $dir.libs/$base.lo.d.
-      #
-      # With libtool 1.5 this exception was removed, and libtool now
-      # generates 2 separate objects for the 2 libraries.  These two
-      # compilations output dependencies in $dir.libs/$base.o.d and
-      # in $dir$base.o.d.  We have to check for both files, because
-      # one of the two compilations can be disabled.  We should prefer
-      # $dir$base.o.d over $dir.libs/$base.o.d because the latter is
-      # automatically cleaned when .libs/ is deleted, while ignoring
-      # the former would cause a distcleancheck panic.
-      tmpdepfile1=$dir.libs/$base.lo.d   # libtool 1.4
-      tmpdepfile2=$dir$base.o.d          # libtool 1.5
-      tmpdepfile3=$dir.libs/$base.o.d    # libtool 1.5
-      tmpdepfile4=$dir.libs/$base.d      # Compaq CCC V6.2-504
-      "$@" -Wc,-MD
-   else
-      tmpdepfile1=$dir$base.o.d
-      tmpdepfile2=$dir$base.d
-      tmpdepfile3=$dir$base.d
-      tmpdepfile4=$dir$base.d
-      "$@" -MD
-   fi
-
-   stat=$?
-   if test $stat -eq 0; then :
-   else
-      rm -f "$tmpdepfile1" "$tmpdepfile2" "$tmpdepfile3" "$tmpdepfile4"
-      exit $stat
-   fi
-
-   for tmpdepfile in "$tmpdepfile1" "$tmpdepfile2" "$tmpdepfile3" "$tmpdepfile4"
-   do
-     test -f "$tmpdepfile" && break
-   done
-   if test -f "$tmpdepfile"; then
-      sed -e "s,^.*\.[a-z]*:,$object:," < "$tmpdepfile" > "$depfile"
-      # That's a tab and a space in the [].
-      sed -e 's,^.*\.[a-z]*:[	 ]*,,' -e 's,$,:,' < "$tmpdepfile" >> "$depfile"
-   else
-      echo "#dummy" > "$depfile"
-   fi
-   rm -f "$tmpdepfile"
-   ;;
+  # The Tru64 compiler uses -MD to generate dependencies as a side
+  # effect.  'cc -MD -o foo.o ...' puts the dependencies into 'foo.o.d'.
+  # At least on Alpha/Redhat 6.1, Compaq CCC V6.2-504 seems to put
+  # dependencies in 'foo.d' instead, so we check for that too.
+  # Subdirectories are respected.
+  set_dir_from  "$object"
+  set_base_from "$object"
+
+  if test "$libtool" = yes; then
+    # Libtool generates 2 separate objects for the 2 libraries.  These
+    # two compilations output dependencies in $dir.libs/$base.o.d and
+    # in $dir$base.o.d.  We have to check for both files, because
+    # one of the two compilations can be disabled.  We should prefer
+    # $dir$base.o.d over $dir.libs/$base.o.d because the latter is
+    # automatically cleaned when .libs/ is deleted, while ignoring
+    # the former would cause a distcleancheck panic.
+    tmpdepfile1=$dir$base.o.d          # libtool 1.5
+    tmpdepfile2=$dir.libs/$base.o.d    # Likewise.
+    tmpdepfile3=$dir.libs/$base.d      # Compaq CCC V6.2-504
+    "$@" -Wc,-MD
+  else
+    tmpdepfile1=$dir$base.d
+    tmpdepfile2=$dir$base.d
+    tmpdepfile3=$dir$base.d
+    "$@" -MD
+  fi
+
+  stat=$?
+  if test $stat -ne 0; then
+    rm -f "$tmpdepfile1" "$tmpdepfile2" "$tmpdepfile3"
+    exit $stat
+  fi
+
+  for tmpdepfile in "$tmpdepfile1" "$tmpdepfile2" "$tmpdepfile3"
+  do
+    test -f "$tmpdepfile" && break
+  done
+  # Same post-processing that is required for AIX mode.
+  aix_post_process_depfile
+  ;;
+
+msvc7)
+  if test "$libtool" = yes; then
+    showIncludes=-Wc,-showIncludes
+  else
+    showIncludes=-showIncludes
+  fi
+  "$@" $showIncludes > "$tmpdepfile"
+  stat=$?
+  grep -v '^Note: including file: ' "$tmpdepfile"
+  if test $stat -ne 0; then
+    rm -f "$tmpdepfile"
+    exit $stat
+  fi
+  rm -f "$depfile"
+  echo "$object : \\" > "$depfile"
+  # The first sed program below extracts the file names and escapes
+  # backslashes for cygpath.  The second sed program outputs the file
+  # name when reading, but also accumulates all include files in the
+  # hold buffer in order to output them again at the end.  This only
+  # works with sed implementations that can handle large buffers.
+  sed < "$tmpdepfile" -n '
+/^Note: including file:  *\(.*\)/ {
+  s//\1/
+  s/\\/\\\\/g
+  p
+}' | $cygpath_u | sort -u | sed -n '
+s/ /\\ /g
+s/\(.*\)/'"$tab"'\1 \\/p
+s/.\(.*\) \\/\1:/
+H
+$ {
+  s/.*/'"$tab"'/
+  G
+  p
+}' >> "$depfile"
+  echo >> "$depfile" # make sure the fragment doesn't end with a backslash
+  rm -f "$tmpdepfile"
+  ;;
+
+msvc7msys)
+  # This case exists only to let depend.m4 do its work.  It works by
+  # looking at the text of this script.  This case will never be run,
+  # since it is checked for above.
+  exit 1
+  ;;
 
 #nosideeffect)
   # This comment above is used by automake to tell side-effect
@@ -422,7 +580,7 @@ dashmstdout)
     shift
   fi
 
-  # Remove `-o $object'.
+  # Remove '-o $object'.
   IFS=" "
   for arg
   do
@@ -442,18 +600,18 @@ dashmstdout)
   done
 
   test -z "$dashmflag" && dashmflag=-M
-  # Require at least two characters before searching for `:'
+  # Require at least two characters before searching for ':'
   # in the target name.  This is to cope with DOS-style filenames:
-  # a dependency such as `c:/foo/bar' could be seen as target `c' otherwise.
+  # a dependency such as 'c:/foo/bar' could be seen as target 'c' otherwise.
   "$@" $dashmflag |
-    sed 's:^[  ]*[^: ][^:][^:]*\:[    ]*:'"$object"'\: :' > "$tmpdepfile"
+    sed "s|^[$tab ]*[^:$tab ][^:][^:]*:[$tab ]*|$object: |" > "$tmpdepfile"
   rm -f "$depfile"
   cat < "$tmpdepfile" > "$depfile"
-  tr ' ' '
-' < "$tmpdepfile" | \
-## Some versions of the HPUX 10.20 sed can't process this invocation
-## correctly.  Breaking it into two sed invocations is a workaround.
-    sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' | sed -e 's/$/ :/' >> "$depfile"
+  # Some versions of the HPUX 10.20 sed can't process this sed invocation
+  # correctly.  Breaking it into two sed invocations is a workaround.
+  tr ' ' "$nl" < "$tmpdepfile" \
+    | sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' \
+    | sed -e 's/$/ :/' >> "$depfile"
   rm -f "$tmpdepfile"
   ;;
 
@@ -503,12 +661,15 @@ makedepend)
   touch "$tmpdepfile"
   ${MAKEDEPEND-makedepend} -o"$obj_suffix" -f"$tmpdepfile" "$@"
   rm -f "$depfile"
-  cat < "$tmpdepfile" > "$depfile"
-  sed '1,2d' "$tmpdepfile" | tr ' ' '
-' | \
-## Some versions of the HPUX 10.20 sed can't process this invocation
-## correctly.  Breaking it into two sed invocations is a workaround.
-    sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' | sed -e 's/$/ :/' >> "$depfile"
+  # makedepend may prepend the VPATH from the source file name to the object.
+  # No need to regex-escape $object, excess matching of '.' is harmless.
+  sed "s|^.*\($object *:\)|\1|" "$tmpdepfile" > "$depfile"
+  # Some versions of the HPUX 10.20 sed can't process the last invocation
+  # correctly.  Breaking it into two sed invocations is a workaround.
+  sed '1,2d' "$tmpdepfile" \
+    | tr ' ' "$nl" \
+    | sed -e 's/^\\$//' -e '/^$/d' -e '/:$/d' \
+    | sed -e 's/$/ :/' >> "$depfile"
   rm -f "$tmpdepfile" "$tmpdepfile".bak
   ;;
 
@@ -525,7 +686,7 @@ cpp)
     shift
   fi
 
-  # Remove `-o $object'.
+  # Remove '-o $object'.
   IFS=" "
   for arg
   do
@@ -544,10 +705,10 @@ cpp)
     esac
   done
 
-  "$@" -E |
-    sed -n -e '/^# [0-9][0-9]* "\([^"]*\)".*/ s:: \1 \\:p' \
-       -e '/^#line [0-9][0-9]* "\([^"]*\)".*/ s:: \1 \\:p' |
-    sed '$ s: \\$::' > "$tmpdepfile"
+  "$@" -E \
+    | sed -n -e '/^# [0-9][0-9]* "\([^"]*\)".*/ s:: \1 \\:p' \
+             -e '/^#line [0-9][0-9]* "\([^"]*\)".*/ s:: \1 \\:p' \
+    | sed '$ s: \\$::' > "$tmpdepfile"
   rm -f "$depfile"
   echo "$object : \\" > "$depfile"
   cat < "$tmpdepfile" >> "$depfile"
@@ -579,23 +740,23 @@ msvisualcpp)
       shift
       ;;
     "-Gm"|"/Gm"|"-Gi"|"/Gi"|"-ZI"|"/ZI")
-	set fnord "$@"
-	shift
-	shift
-	;;
+        set fnord "$@"
+        shift
+        shift
+        ;;
     *)
-	set fnord "$@" "$arg"
-	shift
-	shift
-	;;
+        set fnord "$@" "$arg"
+        shift
+        shift
+        ;;
     esac
   done
   "$@" -E 2>/dev/null |
   sed -n '/^#line [0-9][0-9]* "\([^"]*\)"/ s::\1:p' | $cygpath_u | sort -u > "$tmpdepfile"
   rm -f "$depfile"
   echo "$object : \\" > "$depfile"
-  sed < "$tmpdepfile" -n -e 's% %\\ %g' -e '/^\(.*\)$/ s::	\1 \\:p' >> "$depfile"
-  echo "	" >> "$depfile"
+  sed < "$tmpdepfile" -n -e 's% %\\ %g' -e '/^\(.*\)$/ s::'"$tab"'\1 \\:p' >> "$depfile"
+  echo "$tab" >> "$depfile"
   sed < "$tmpdepfile" -n -e 's% %\\ %g' -e '/^\(.*\)$/ s::\1\::p' >> "$depfile"
   rm -f "$tmpdepfile"
   ;;
@@ -622,9 +783,9 @@ exit 0
 # Local Variables:
 # mode: shell-script
 # sh-indentation: 2
-# eval: (add-hook 'write-file-hooks 'time-stamp)
+# eval: (add-hook 'before-save-hook 'time-stamp)
 # time-stamp-start: "scriptversion="
 # time-stamp-format: "%:y-%02m-%02d.%02H"
-# time-stamp-time-zone: "UTC"
+# time-stamp-time-zone: "UTC0"
 # time-stamp-end: "; # UTC"
 # End:
diff --git a/src/Makefile.am b/src/Makefile.am
index 5cdc3cb6..ada5ce5a 100755
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -38,9 +38,9 @@ util/util_area_intersection.f90\
 util/util_poisson.f90\
 util/util_pop_array.f90\
 util/util_push_array.f90\
-util/util_traverse_pop.f90\
+util/util_traverse_pop_array.f90\
 util/util_destroy_list.f90\
-util/util_init_list.f90\
+util/util_init_array.f90\
 util/util_perlin_noise.f90\
 io/io_read_const.f90\
 io/io_get_token.f90\
@@ -60,9 +60,7 @@ io/io_crater_profile.f90\
 io/io_updatePbar.f90\
 io/io_resetPbar.f90\
 io/io_splash.f90\
-io/io_write_age.f90\
 io/io_write_pindex_map.f90\
-io/io_write_age_depth.f90\
 ejecta/ejecta_emplace.f90\
 ejecta/ejecta_ray_pattern.f90\
 ejecta/ejecta_ray_pattern_func.f90\
diff --git a/src/io/io_write_age.f90 b/src/io/io_write_age.f90
index 2f102188..78e1c4b6 100644
--- a/src/io/io_write_age.f90
+++ b/src/io/io_write_age.f90
@@ -38,7 +38,8 @@ subroutine io_write_age(user,surf,n_size,icrater,ncrat)
    integer(kind=8)                                     :: recsize
    real(SP)                                            :: stmp
    real(SP)                                            :: agetot, age_weighted
-   type(regolisttype),pointer                          :: current => null()
+   !type(regolisttype),pointer                          :: current => null()
+   type(regodatatype),dimension(:),allocatable         :: current
    real(DP)                                            :: depth, depth_prev
    real(SP)                                            :: recyclratio
    ! Output multiple "comphisto" files
@@ -55,8 +56,10 @@ subroutine io_write_age(user,surf,n_size,icrater,ncrat)
          
          depth       = 0.0 
          depth_prev  = 0.0 
-         current => surf(i,j)%regolayer
-         age_prev(:) = current%regodata%age(:)
+         !current => surf(i,j)%regolayer
+         !current = surf(i,j)%regolayer(:)
+         allocate(current,source=surf(i,j)%regolayer(:))
+         age_prev(:) = current%age(:)
          agedepthtot = 0.0_SP
          do 
           if (depth > sdepth) then
@@ -66,10 +69,10 @@ subroutine io_write_age(user,surf,n_size,icrater,ncrat)
              exit
            end if
            depth_prev     = depth
-           depth          = depth + current%regodata%thickness
-           agedepthtot(:) = agedepthtot(:) + current%regodata%age(:)
-           age_prev(:)    = current%regodata%age(:)
-           current => current%next
+           depth          = depth + current%thickness
+           agedepthtot(:) = agedepthtot(:) + current%age(:)
+           age_prev(:)    = current%age(:)
+           !current => current%next
          end do
 
          age_weighted = 0.0_SP
diff --git a/src/io/io_write_regotrack.f90 b/src/io/io_write_regotrack.f90
index e21ad5e8..a2f8fd41 100644
--- a/src/io/io_write_regotrack.f90
+++ b/src/io/io_write_regotrack.f90
@@ -77,10 +77,10 @@ subroutine io_write_regotrack(user,surf)
             ! comp(k) = current%regodata%comp
             ! age(:,k) = current%regodata%age(:)
             ! current => current%next
-            meltfrac(k) = current%meltfrac
-            thickness(k) = current%thickness
-            comp(k) = current%comp
-            age(:,k) = current%age(:)
+            meltfrac(k) = current(k)%meltfrac
+            thickness(k) = current(k)%thickness
+            comp(k) = current(k)%comp
+            age(:,k) = current(k)%age(:)
 
          end do
          write(FMELT) meltfrac(:)
diff --git a/src/regolith/module_regolith.f90 b/src/regolith/module_regolith.f90
index 5aa2a944..d9941907 100644
--- a/src/regolith/module_regolith.f90
+++ b/src/regolith/module_regolith.f90
@@ -269,7 +269,7 @@ subroutine regolith_superdomain(user,crater,domain,regolayer,ejdistribution,xpi,
      type(usertype),intent(in)      :: user
      type(cratertype),intent(inout) :: crater
      type(domaintype),intent(in)    :: domain
-     type(regolisttype),pointer     :: regolayer
+     type(regodatatype),dimension(:),allocatable,intent(inout)       :: regolayer
      real(DP),intent(in)            :: ejdistribution 
      integer(I4B),intent(in)        :: xpi, ypi
      real(DP),intent(in)            :: age
diff --git a/src/regolith/regolith_streamtube_head.f90 b/src/regolith/regolith_streamtube_head.f90
index 7624d742..cb7568fc 100644
--- a/src/regolith/regolith_streamtube_head.f90
+++ b/src/regolith/regolith_streamtube_head.f90
@@ -30,7 +30,8 @@ subroutine regolith_streamtube_head(user,surfi,deltar,totmare,tots,age_collector
    real(SP),dimension(:),intent(inout) :: age_collector
  
    ! internal variables
-   type(regolisttype),pointer :: current
+   !type(regolisttype),pointer :: current
+   type(regodatatype),dimension(:),allocatable :: current
    real(DP),parameter :: vratio = sqrt(2.0_DP)/2.0_DP ! Unfortunately, the approximate function that is used to get the size of a stream
                                                       ! tube with a constraint of CTEM's ejecta blanket thickness is slightly different
                                                       ! from the analytical function that we use here to approximate the stream tube's 
@@ -41,8 +42,10 @@ subroutine regolith_streamtube_head(user,surfi,deltar,totmare,tots,age_collector
    ! melt collector
    real(DP) :: recyratio
 
-   current => surfi%regolayer
-   z = current%regodata%thickness
+   !current => surfi%regolayer
+   !current = surfi%regolayer
+   allocate(current,source=surfi%regolayer)
+   z = current%thickness
    vsgly = vratio * PI * deltar**3
    tothead = 0._DP
    totmarehead = 0._DP
@@ -55,29 +58,29 @@ subroutine regolith_streamtube_head(user,surfi,deltar,totmare,tots,age_collector
 
    if (zend >= zmax) then ! Stream tube's head is inside the 1st layer.
       tots = tots + vsgly
-      totmare = totmare + vsgly * current%regodata%comp
-      recyratio = vsgly / (user%pix**2) /current%regodata%thickness
-      age_collector(:) = age_collector(:) + current%regodata%age(:) * recyratio
+      totmare = totmare + vsgly * current%comp
+      recyratio = vsgly / (user%pix**2) /current%thickness
+      age_collector(:) = age_collector(:) + current%age(:) * recyratio
    else ! head is not intersected with layers. 
 
    do
-      if (.not. associated(current%next)) exit
+      ! if (.not. associated(current%next)) exit
       
       if (zend < zmax) then 
          vhead = regolith_circle_sector_func(deltar,zstart,zend)
          tothead = tothead + vhead * vratio 
-         totmarehead = totmarehead + vhead * vratio * current%regodata%comp
-         recyratio = vhead * vratio / (user%pix**2) / current%regodata%thickness
-         age_collector(:) = age_collector(:) + current%regodata%age(:) * recyratio
-         current => current%next
-         z = z + current%regodata%thickness
+         totmarehead = totmarehead + vhead * vratio * current%comp
+         recyratio = vhead * vratio / (user%pix**2) / current%thickness
+         age_collector(:) = age_collector(:) + current%age(:) * recyratio
+         !current => current%next
+         z = z + current%thickness
          zstart = zend
          zend = z
       else 
-         totmarehead = totmarehead + (vsgly-tothead) * current%regodata%comp
+         totmarehead = totmarehead + (vsgly-tothead) * current%comp
          tothead = vsgly
-         recyratio = (vsgly - tothead) / (user%pix**2) / current%regodata%thickness
-         age_collector(:) = age_collector(:) + current%regodata%age(:) * recyratio
+         recyratio = (vsgly - tothead) / (user%pix**2) / current%thickness
+         age_collector(:) = age_collector(:) + current%age(:) * recyratio
          exit
       end if
    end do
diff --git a/src/regolith/regolith_superdomain.f90 b/src/regolith/regolith_superdomain.f90
index 062b0be4..ba48f482 100644
--- a/src/regolith/regolith_superdomain.f90
+++ b/src/regolith/regolith_superdomain.f90
@@ -29,7 +29,7 @@ subroutine regolith_superdomain(user,crater,domain,regolayer,ejdistribution,xpi,
    type(usertype),intent(in)             :: user
    type(cratertype),intent(inout)        :: crater
    type(domaintype),intent(in)           :: domain
-   type(regolisttype),pointer            :: regolayer
+   type(regodatatype),dimension(:),allocatable,intent(inout)            :: regolayer
    real(DP),intent(in)                   :: ejdistribution
    integer(I4B),intent(in)               :: xpi, ypi
    real(DP),intent(in)                   :: age
diff --git a/src/util/module_util.f90 b/src/util/module_util.f90
index 78720ef6..75b9731b 100644
--- a/src/util/module_util.f90
+++ b/src/util/module_util.f90
@@ -46,8 +46,8 @@ module module_util
    subroutine util_push_array(regolayer,newregodata)
    use module_globals
    implicit none
-   type(regodatatype),dimension(:),allocatable :: regolayer
-   type(regodatatype),dimension(:),allocatable,intent(in) :: newregodata
+   type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
+   type(regodatatype),intent(in) :: newregodata
    end subroutine util_push_array
 end interface
 
@@ -55,7 +55,7 @@ end subroutine util_push_array
    subroutine util_pop_array(regolayer,oldregodata)
    use module_globals
    implicit none
-   type(regodatatype),dimension(:),allocatable :: regolayer
+   type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
    type(regodatatype),intent(out) :: oldregodata
    end subroutine util_pop_array
 end interface
@@ -70,15 +70,26 @@ end subroutine util_pop_array
 !    end subroutine util_pop
 ! end interface
 
+! interface
+!    subroutine util_traverse_pop(regolayer,traverse_depth,poppedlist)
+!    use module_globals
+!    implicit none
+!    !type(regolisttype),pointer :: regolayer
+!    type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
+!    real(DP),intent(in)         :: traverse_depth
+!    !type(regolisttype),pointer :: poppedlist
+!    !type(regodatatype),dimension(:),allocatable,intent(out) :: poppedarray
+!    end subroutine 
+! end interface
+
 interface
-   subroutine util_traverse_pop(regolayer,traverse_depth,poppedlist)
+   subroutine util_traverse_pop_array(regolayer,traverse_depth,poppedarray)
    use module_globals
    implicit none
-   !type(regolisttype),pointer :: regolayer
-   type(regodatatype),dimension(:),allocatable :: regolayer
-   real(DP),intent(in)         :: traverse_depth
-   type(regolisttype),pointer :: poppedlist
-   end subroutine 
+   type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
+   real(DP),intent(in) :: traverse_depth
+   type(regodatatype),dimension(:),allocatable,intent(out) :: poppedarray
+   end subroutine
 end interface
 
 interface
@@ -89,13 +100,22 @@ subroutine util_destroy_list(regolayer)
    end subroutine util_destroy_list
 end interface
 
+! interface
+!    subroutine util_init_list(regolayer,initstat)
+!    use module_globals
+!    implicit none
+!    type(regolisttype),pointer :: regolayer
+!    logical, intent(out)     :: initstat
+!    end subroutine util_init_list
+! end interface
+
 interface
-   subroutine util_init_list(regolayer,initstat)
+   subroutine util_init_array(regolayer,initstat)
    use module_globals
    implicit none
-   type(regolisttype),pointer :: regolayer
+   type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
    logical, intent(out)     :: initstat
-   end subroutine util_init_list
+   end subroutine util_init_array
 end interface
 
 interface
diff --git a/src/util/util_init_array.f90 b/src/util/util_init_array.f90
new file mode 100644
index 00000000..e1c2dc52
--- /dev/null
+++ b/src/util/util_init_array.f90
@@ -0,0 +1,61 @@
+!**********************************************************************************************************************************
+!
+!  Unit Name   : util_init_array
+!  Unit Type   : subroutine
+!  Project     : CTEM
+!  Language    : Fortran 2003
+!
+!  Description : Initialize an new allocatable array
+!  
+!
+!  Input
+!    Arguments : regolayer :: array
+!                oldlayer  :: old layer to pop off of the top of the stack
+!
+!  Output
+!    Arguments :
+!           
+! 
+!  Notes       : 
+!
+!**********************************************************************************************************************************
+subroutine util_init_array(regolayer,initstat)
+    use module_globals
+    use module_util, EXCEPT_THIS_ONE => util_init_array
+    implicit none
+ 
+    ! Arguments
+    type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
+    logical, intent(out)       :: initstat
+ 
+    ! Internal variables
+    integer(I4B) :: allocstat 
+ 
+    ! Executable code
+    initstat = .false.
+    ! if (.not. associated(regolayer)) then
+    !    allocate(regolayer, STAT=allocstat)
+    !    if (allocstat == 0) then
+    !       initstat = .true.
+    !       nullify(regolayer%next)
+          ! regolayer%regodata%thickness = sqrt(VBIG) ! This generates a buffer layer that the model should never reach if the run is structured properly
+          ! regolayer%regodata%comp = 0.0_DP
+          ! regolayer%regodata%meltfrac = 0.0_DP
+          ! regolayer%regodata%porosity = 0.0_DP
+          ! regolayer%regodata%age(:)   = 0.0_SP
+    if (allocated(regolayer)) deallocate(regolayer)
+    allocate(regolayer(1))
+    regolayer(1)%thickness = sqrt(VBIG) ! This generates a buffer layer that the model should never reach if the run is structured properly
+    regolayer(1)%comp = 0.0_DP
+    regolayer(1)%meltfrac = 0.0_DP
+    regolayer(1)%porosity = 0.0_DP
+    regolayer(1)%age(:)   = 0.0_SP
+    !    else
+    !       write(*,*) 'util_init_list: Initialization failed. Exhausted memory.'
+    !    end if
+    ! else
+    !    write(*,*) 'util_init_list: Initialization failed. Regolayer already associated.'
+    ! end if
+ 
+    return
+ end subroutine util_init_array
\ No newline at end of file
diff --git a/src/util/util_pop_array.f90 b/src/util/util_pop_array.f90
index 7d148d1e..9fb4ec77 100644
--- a/src/util/util_pop_array.f90
+++ b/src/util/util_pop_array.f90
@@ -25,19 +25,19 @@ subroutine util_pop_array(regolayer,oldregodata)
     implicit none
 
     ! Arguments
-    type(regodatatype),dimension(:),allocatable :: regolayer
+    type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
     type(regodatatype),intent(out) :: oldregodata
 
     ! Internal variables
     type(regodatatype), dimension(:), allocatable :: newlayer
-    integer(I4B) :: allocstat
     integer(I4B) :: nold
 
     ! Executable code
 
     nold = size(regolayer)
 
-    allocate(newlayer(nold-1), stat=allocstat)
-    newlayer(1:nold-1) = regolayer(1:nold-1) ! could also be 2:nold depending on if top or bottom is popped off
+    allocate(newlayer(nold-1),source=regolayer(1:nold-1))
+    !newlayer(1:nold-1) = regolayer(1:nold-1) ! could also be 2:nold depending on if top or bottom is popped off
+    oldregodata = regolayer(nold)
     call move_alloc(newlayer, regolayer)
 end subroutine util_pop_array
\ No newline at end of file
diff --git a/src/util/util_push_array.f90 b/src/util/util_push_array.f90
index c1aea892..958f207a 100644
--- a/src/util/util_push_array.f90
+++ b/src/util/util_push_array.f90
@@ -25,21 +25,20 @@ subroutine util_push_array(regolayer,newregodata)
     implicit none
  
     ! Arguments
-    type(regodatatype),dimension(:),allocatable :: regolayer
-    type(regodatatype),dimension(:),allocatable :: newregodata
+    type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
+    type(regodatatype),intent(in) :: newregodata
 
     ! Internal variables
     type(regodatatype), dimension(:), allocatable :: newlayer
-    integer(I4B) :: allocstat
     integer(I4B) :: nold
 
     ! Executable code
 
     nold = size(regolayer)
 
-    allocate(newregodata(nold+1), stat=allocstat)
+    allocate(newlayer(nold+1))
     newlayer(1:nold) = regolayer(1:nold)
-    newlayer(nold+1) = newregodata(:) ! need to see if this adds to the top or bottom of the layer stack
+    newlayer(nold+1) = newregodata ! need to see if this adds to the top or bottom of the layer stack
     call move_alloc(newlayer, regolayer)
 end subroutine util_push_array
 
diff --git a/src/util/util_traverse_pop.f90 b/src/util/util_traverse_pop.f90
index f4725482..8b208739 100755
--- a/src/util/util_traverse_pop.f90
+++ b/src/util/util_traverse_pop.f90
@@ -60,10 +60,11 @@ subroutine util_traverse_pop(regolayer,traverse_depth,poppedlist)
    implicit none
 
    ! Arguments
-   !type(regolisttype),pointer   :: regolayer
-   type(regodatatype),dimension(:),allocatable :: regolayer
+   type(regolisttype),pointer   :: regolayer
+   type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
    real(DP),intent(in)          :: traverse_depth
    type(regolisttype),pointer   :: poppedlist 
+   type(regodatatype),dimension(:),allocatable,intent(out) :: poppedarray
 
    ! Internal variables
    real(DP)                    :: z,depth,dz
@@ -71,7 +72,7 @@ subroutine util_traverse_pop(regolayer,traverse_depth,poppedlist)
    logical                     :: initstat
    real(DP)                    :: recyratio
 
-   depth = regolayer%regodata%thickness
+   depth = regolayer%thickness
    dz = 0._DP
    z = traverse_depth
    poppedlist => null()
@@ -90,19 +91,19 @@ subroutine util_traverse_pop(regolayer,traverse_depth,poppedlist)
 
        if (z <= depth) then
           dz = depth - z
-          oldregodata                  = regolayer%regodata
+          oldregodata                  = regolayer
           oldregodata%thickness        = z
-          oldregodata%age(:)           = z / regolayer%regodata%thickness * regolayer%regodata%age(:)
-          recyratio                    = dz / regolayer%regodata%thickness
-          regolayer%regodata%age(:)    = recyratio * regolayer%regodata%age(:)
-          regolayer%regodata%thickness = dz
+          oldregodata%age(:)           = z / regolayer%thickness * regolayer%age(:)
+          recyratio                    = dz / regolayer%thickness
+          regolayer%age(:)    = recyratio * regolayer%age(:)
+          regolayer%thickness = dz
           call util_push_array(poppedlist,oldregodata)
           exit
        else
-          z = z - regolayer%regodata%thickness
+          z = z - regolayer%thickness
           call util_pop_array(regolayer,oldregodata)
           call util_push_array(poppedlist,oldregodata)
-          depth = regolayer%regodata%thickness
+          depth = regolayer%thickness
        end if
       
       end do
diff --git a/src/util/util_traverse_pop_array.f90 b/src/util/util_traverse_pop_array.f90
new file mode 100644
index 00000000..15bebc5e
--- /dev/null
+++ b/src/util/util_traverse_pop_array.f90
@@ -0,0 +1,87 @@
+!**********************************************************************************************************************************
+!
+!  Unit Name   : util_traverse_pop_array
+!  Unit Type   : function
+!  Project     : CTEM
+!  Language    : Fortran 2003
+!
+!  Description : Removes all layers down to a given depth. Cuts a layer if the depth ends in the middle of an old layer.
+!  
+!
+!  Input
+!    Arguments : 
+!
+!  Output
+!    Arguments : surf  
+!           
+! 
+!  Notes       :  Popped list will be in reversed order from the original list
+!
+!**********************************************************************************************************************************
+subroutine util_traverse_pop_array(regolayer,traverse_depth,poppedarray)
+    use module_globals
+    use module_util, EXCEPT_THIS_ONE => util_traverse_pop_array
+    implicit none
+ 
+    ! Arguments
+    !type(regolisttype),pointer   :: regolayer
+    type(regodatatype),dimension(:),allocatable,intent(inout) :: regolayer
+    real(DP),intent(in)          :: traverse_depth
+    !type(regolisttype),pointer   :: poppedlist 
+    type(regodatatype),dimension(:),allocatable,intent(out) :: poppedarray
+ 
+    ! Internal variables
+    real(DP)                    :: z,depth,dz
+    type(regodatatype)          :: oldregodata
+    logical                     :: initstat
+    real(DP)                    :: recyratio
+    integer(I4B)                :: i, N, maxi
+ 
+    N = size(regolayer)
+    depth = regolayer(N)%thickness
+    dz = 0._DP
+    z = traverse_depth
+    
+ 
+  
+    ! Initialize popped array
+    !call util_init_array(poppedarray,initstat)
+ 
+    
+    !if (initstat) then
+    i = N
+    do
+        depth = depth + regolayer(i)%depth
+        if (depth > traverse_depth) then
+            maxi = i
+            exit
+        else
+            i = i - 1
+        end if
+    end do
+
+
+    allocate(poppedarray,source=regolayer(maxi:N))
+
+
+    depth = regolayer(maxi)%depth
+
+    ! if (z <= depth) then
+    !     dz = depth - z
+    oldregodata                  = regolayer(maxi)
+    oldregodata%thickness        = z
+    oldregodata%age(:)           = z / regolayer(maxi)%thickness * regolayer(maxi)%age(:)
+    recyratio                    = dz / regolayer(maxi)%thickness
+    regolayer(maxi)%age(:)    = recyratio * regolayer(maxi)%age(:)
+    regolayer(maxi)%thickness = dz
+    call util_push_array(poppedarray,oldregodata)
+    ! else
+    !     z = z - regolayer%thickness
+    !     call util_pop_array(regolayer,oldregodata)
+    !     call util_push_array(poppedarray,oldregodata)
+    !     depth = regolayer%thickness
+    ! end if
+       
+    return
+ end subroutine util_traverse_pop_array
+ 
\ No newline at end of file