[svn-r21101] HDFFV-7639

Purpose:

    Remove H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS and
    H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS #defines from source.

Description:

    Two advanced parallel functionalities, special collective IO and
    complex derived datatypes, are not supported by older
    implementations of mpi, and thus our code limits the use of these
    features with #ifdefs and has checks in configure to set them (or
    not). Unfortunately, configure can't actually run a parallel check
    to see if these features are working (nor not) so it resorts to
    looking in the config files where they are explicity enabled or
    disabled based on versions of mpi, sytems being built on, or for
    no documented reason at all (i.e. just set to on or off as some
    'default'). Overriding these settings is easy if need be, provided
    it is known that it needs to be done to get improved performance,
    and oftentimes it is not.

    Most new MPI implementations successfully handle the functionality
    requested when these #defines are set, and many of the "turn these
    features off" cases in the config files are for old (> 5 years)
    versions of MPI and retired systems (such as NCSA's tungsten).

    Therefore, the decision has been made to remove the support for
    these old versions of MPI and systems that cannot handle these
    behaviors. The #ifdefs and supporting setup in the config/ files
    and configure script has been removed, and the code executed when
    these options were not set removed from the source.

    In passing, this commit also cleans up some whitespace issues in
    both t_mpi.c and H5Dmpio.c. Furthermore, in t_mpi.c, the special
    collective IO test was not getting regularly run due to it being
    written to work only with four processes (we regularly test with
    six, previously with three), and thus it failed when actually run
    due to an out of bounds data buffer assignment. It has been
    modified to run at any number of processes greater than four, and
    the memory problem has been fixed so the test passes.

Tested:

    jam, h5committest, ember

17 files changed, 288 insertions, 794 deletions

diff --git a/MANIFEST b/MANIFEST
index e19d1b4..e51a7c7 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -105,7 +105,6 @@
 ./config/linux-gnulibc1
 ./config/linux-gnulibc2
 ./config/lt_vers.am
-./config/mpich
 ./config/nec-superux14.1
 ./config/Makefile.am.blank
 ./config/pgi-fflags
diff --git a/config/cmake/H5pubconf.h.in b/config/cmake/H5pubconf.h.in
index 8b8bf30..ae2e1a0 100644
--- a/config/cmake/H5pubconf.h.in
+++ b/config/cmake/H5pubconf.h.in
@@ -514,17 +514,10 @@
 /* Define if the metadata trace file code is to be compiled in */
 #cmakedefine H5_METADATA_TRACE_FILE @H5_METADATA_TRACE_FILE@
 
-/* Define if your system can handle complicated MPI derived datatype
-   correctly. */
-#cmakedefine H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS @H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS@
-
 /* Define if your system's `MPI_File_set_size' function works for files over
    2GB. */
 #cmakedefine H5_MPI_FILE_SET_SIZE_BIG @H5_MPI_FILE_SET_SIZE_BIG@
 
-/* Define if your system can handle special collective IO properly. */
-#cmakedefine H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS @H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS@
-
 /* Define if we can violate pointer alignment restrictions */
 #cmakedefine H5_NO_ALIGNMENT_RESTRICTIONS @H5_NO_ALIGNMENT_RESTRICTIONS@
 
diff --git a/config/ia64-linux-gnu b/config/ia64-linux-gnu
index 519d0fc..9f1b262 100644
--- a/config/ia64-linux-gnu
+++ b/config/ia64-linux-gnu
@@ -142,12 +142,3 @@ case $CXX_BASENAME in
 	PROFILE_CPPFLAGS=
 	;;
 esac
-
-# Check MPICH settings
-. $srcdir/config/mpich
-#Uncomment the next line if your system doesn't support MPI complex derived datatype.
-#hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype_works='no'}
-#Comment out the following line if your system supports collective IO when some processes
-#don't have any contributions to IOs.
-hdf5_cv_mpi_special_collective_io_works=${hdf5_cv_mpi_special_collective_io_works='no'}
-
diff --git a/config/ibm-aix b/config/ibm-aix
index a94be4b..7022ab6 100644
--- a/config/ibm-aix
+++ b/config/ibm-aix
@@ -142,11 +142,6 @@ if test "X-" = "X-$f9x_flags_set"; then
   f9x_flags_set=yes
 fi
 
-# With poe version 3.2.0.19 or lower(using lpp -l all | grep ppe.poe to check the version number, 
-# IBM MPI-IO implementation has a bug, 
-#it cannot generate correct MPI derived datatype. Please uncomment the following line:
-#hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype_works='no'}
-
 # The default C++ compiler
 
 # Use AIX supplied C++ compiler by default.
diff --git a/config/irix6.x b/config/irix6.x
index 9bd9c4c..8179b86 100644
--- a/config/irix6.x
+++ b/config/irix6.x
@@ -171,26 +171,6 @@ hdf5_cv_ulong_to_fp_bottom_bit_accurate=${hdf5_cv_ulong_to_fp_bottom_bit_accurat
 hdf5_cv_ldouble_to_integer_accurate=${hdf5_cv_ldouble_to_integer_accurate='no'}
 hdf5_cv_integer_to_ldouble_accurate=${hdf5_cv_integer_to_ldouble_accurate='no'}
 
-# For IRIX 6.5, any version that is older than MIPSpro 7.3.1.3m, 
-# the MPI derived datatype is not working.
-# Versions 7.4.2m or newer work.
-# Up to version 7.4.4m, it cannot handle collective IO with non-contribution 
-# of some processes.
-# Fix $hdf5_cv_mpi_complex_derived_datatype_works if it is not set and is using cc.
-if [ -z "$hdf5_cv_mpi_complex_derived_datatype_works" -a $CC_BASENAME = cc ]; then
-    ccversion=`$CC -version 2>&1 | sed -e 's/.*Version //p'`
-    ccversion1=`echo $ccversion | cut -f1 -d.`
-    ccversion2=`echo $ccversion | cut -f2 -d.`
-    # Assume all versions 7.4.* or newer are okay
-    # and assume ccversion2 is never larger than 99.
-    ccversionval=`expr $ccversion1 \* 100 + $ccversion2`
-    hdf5_cv_mpi_special_collective_io_works='no'
-    if [ $ccversionval -lt 704 ]; then
-        hdf5_cv_mpi_complex_derived_datatype_works='no'
-#        hdf5_cv_mpi_special_collective_io_works='no'
-    fi
-fi
-
 # Set flag to generate alternate code for H5V_log2_gen, to avoid
 # problems with the MIPSpro compiler 7.30 and IRIX64 6.5 (ie. other
 # combinations might work, but haven't been tested)
diff --git a/config/linux-gnulibc1 b/config/linux-gnulibc1
index 8f04cf0..9dcc411 100644
--- a/config/linux-gnulibc1
+++ b/config/linux-gnulibc1
@@ -125,23 +125,6 @@ if test -z "$CXX"; then
   CXX_BASENAME=g++
 fi
 
-# Check MPICH settings
-. $srcdir/config/mpich
-
-# The ChaMPIon on NCSA tungsten doesn't work correctly for either of the following
-# cases:
-#     1. collective I/O when some processes don't have any contributions;
-#     2. complex derived MPI data type.
-if test $CC_BASENAME = cmpicc; then
-  hdf5_cv_mpi_special_collective_io_works=${hdf5_cv_mpi_special_collective_io_works='no'}
-  hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype_works='no'}
-fi
-
-#Comment out the following line if your system supports collective IO when some processes
-#don't have any contributions to IOs.
-hdf5_cv_mpi_special_collective_io_works=${hdf5_cv_mpi_special_collective_io_works='no'}
-hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype_works='no'}
-
 # compiler version strings
 case $CC in
     # whatever matches *pgcc* will also match *gcc*, so this one must come first
diff --git a/config/mpich b/config/mpich
deleted file mode 100644
index 575859e..0000000
--- a/config/mpich
+++ /dev/null
@@ -1,83 +0,0 @@
-#							-*- shell-script -*-
-#
-# Copyright by The HDF Group.
-# Copyright by the Board of Trustees of the University of Illinois.
-# All rights reserved.
-#
-# This file is part of HDF5.  The full HDF5 copyright notice, including
-# terms governing use, modification, and redistribution, is contained in
-# the files COPYING and Copyright.html.  COPYING can be found at the root
-# of the source code distribution tree; Copyright.html can be found at the
-# root level of an installed copy of the electronic HDF5 document set and
-# is linked from the top-level documents page.  It can also be found at
-# http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have
-# access to either file, you may request a copy from help@hdfgroup.org.
-
-# This file should be sourced into configure if the compiler is the
-# MPICH compiler script. It is careful not to do anything if the compiler
-# is not MPICH.
-
-# Check if mpicc can support complicated derived datatype correctly.
-# We know that mpich 1.2.4 and 1.2.5 do not support it correctly.  We assume
-# older versions do not work either.  We don't know of a way of testing its
-# correctness without the risk of hanging the configure process.  So, we
-# set the configure variable hdf5_cv_mpi_complex_derived_datatype_works to no.
-# Notice that this code works only if the mpicc compiler shows its $MPIVERSION
-# properly.  It is confirmed mpicc does that as far back as v1.2.3.
-
-# mpich2 do not support it correctly.  But mpich2 reports small version number
-# indistiguishable from mpich.  Some mpich2 reports blank, some reports 1.0.2.
-
-if [ -z "$hdf5_cv_mpi_complex_derived_datatype_works" ]; then
-    ccversion=`$CC -v 2>/dev/null`
-    # mpich compiler will give "mpicc for 1.2.x ..."
-    if echo "$ccversion" | grep '^mpicc for' > /dev/null ; then
-	# $CC is an MPICH compiler. Grab the version numbers.
-        ccversion=`echo $ccversion | cut -f3 -d' '`
-	case "$ccversion" in
-	    1.2.[0-5]*)
-		hdf5_cv_mpi_complex_derived_datatype_works='no'
-		;;
-	    1.0.2)
-		# mpich2 is recycling the version number, some report
-		# 1.0.2, some report blank.
-		hdf5_cv_mpi_complex_derived_datatype_works='no'
-		;;
-	    "")
-		# got blank ccversion.  Assume it is bad a mpich2.
-		hdf5_cv_mpi_complex_derived_datatype_works='no'
-		;;
-	    *)
-		# assume okay
-		;;
-	esac
-    fi
-fi
-
-if [ -z "$hdf5_cv_mpi_special_collective_io_works" ]; then
-    ccversion=`$CC -v 2>/dev/null`
-    # mpich compiler will give "mpicc for 1.2.x ..."
-    if echo "$ccversion" | grep '^mpicc for' > /dev/null ; then
-	# $CC is an MPICH compiler. Grab the version numbers.
-        ccversion=`echo $ccversion | cut -f3 -d' '`
-	case "$ccversion" in
-	    1.2.[0-6]*)
-		hdf5_cv_mpi_special_collective_io_works='no'
-		;;
-	    1.0.2)
-		# mpich2 is recycling the version number, some report
-		# 1.0.2, some report blank.
-		hdf5_cv_mpi_special_collective_io_works='no'
-		;;
-	    "")
-		# got blank ccversion.  Assume it is bad a mpich2.
-		hdf5_cv_mpi_special_collective_io_works='no'
-		;;
-	    *)
-		# assume okay
-		;;
-	esac
-    fi
-fi
-
-
diff --git a/config/x86_64-redstorm-linux-gnu b/config/x86_64-redstorm-linux-gnu
index 0cd2d73..76f9711 100644
--- a/config/x86_64-redstorm-linux-gnu
+++ b/config/x86_64-redstorm-linux-gnu
@@ -162,5 +162,3 @@ hdf5_cv_ullong_to_fp_cast_works=${hdf5_cv_ullong_to_fp_cast_works='yes'}
 hdf5_cv_ullong_to_ldouble_precision_works=${hdf5_cv_ullong_to_ldouble_precision_works='yes'}
 hdf5_cv_vsnprintf_works=${hdf5_cv_vsnprintf_works='yes'}
 hdf5_cv_fp_to_integer_overflow_works=${hdf5_cv_fp_to_integer_overflow_works='yes'}
-# mpich2 used has derived datatype errors.
-hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype_works='no'}
diff --git a/configure b/configure
index b741fb1..c865948 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.in Id: configure.in 21033 2011-06-26 15:54:32Z hdftest .
+# From configure.in Id: configure.in 21066 2011-07-05 16:23:10Z mamcgree .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.68 for HDF5 1.9.85.
 #
@@ -28015,74 +28015,31 @@ $as_echo "yes" >&6; }
 $as_echo "no" >&6; }
   fi
 
-# Check whether --enable-mpi-size was given.
+                # Check whether --enable-mpi-size was given.
 if test "${enable_mpi_size+set}" = set; then :
   enableval=$enable_mpi_size; MPI_GET_SIZE=$enableval
 fi
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if MPI_File_get_size is enabled" >&5
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if MPI_File_get_size is enabled" >&5
 $as_echo_n "checking if MPI_File_get_size is enabled... " >&6; }
 
 
-case "X-$MPI_GET_SIZE" in
-  X-no)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+  case "X-$MPI_GET_SIZE" in
+    X-no)
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
-    MPI_GET_SIZE=no
-    ;;
-  X-yes|*)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+      MPI_GET_SIZE=no
+      ;;
+    X-yes|*)
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 $as_echo "yes" >&6; }
-    MPI_GET_SIZE=yes
+      MPI_GET_SIZE=yes
 
 $as_echo "#define HAVE_MPI_GET_SIZE 1" >>confdefs.h
 
-    ;;
-esac
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if irregular hyperslab optimization code works inside MPI-IO" >&5
-$as_echo_n "checking if irregular hyperslab optimization code works inside MPI-IO... " >&6; }
-
-if ${hdf5_cv_mpi_complex_derived_datatype_works+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  hdf5_cv_mpi_complex_derived_datatype_works=yes
-fi
-
-
-if test ${hdf5_cv_mpi_complex_derived_datatype_works} = "yes"; then
-
-$as_echo "#define MPI_COMPLEX_DERIVED_DATATYPE_WORKS 1" >>confdefs.h
-
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-fi
-
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if MPI-IO can do collective IO when one or more processes don't do IOs" >&5
-$as_echo_n "checking if MPI-IO can do collective IO when one or more processes don't do IOs... " >&6; }
-
-if ${hdf5_cv_mpi_special_collective_io_works+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  hdf5_cv_mpi_special_collective_io_works=yes
-fi
-
-
-if test ${hdf5_cv_mpi_special_collective_io_works} = "yes"; then
-
-$as_echo "#define MPI_SPECIAL_COLLECTIVE_IO_WORKS 1" >>confdefs.h
-
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-fi
+      ;;
+  esac
 fi
 
 
diff --git a/configure.in b/configure.in
index 1ba585b..222d0f8 100644
--- a/configure.in
+++ b/configure.in
@@ -2796,76 +2796,36 @@ if test -n "$PARALLEL"; then
     AC_MSG_RESULT([no])
   fi
 
-dnl ----------------------------------------------------------------------
-dnl Set the flag to indicate that the MPI_File_get_size() function
-dnl works.  The default is enabled unless the user knows the function
-dnl doesn't work on the system and disables it.  (This flag should be set
-dnl for all machines except for SGI Altix Propack 4 where the function 
-dnl doesn't return correct file size.)
-dnl
-AC_ARG_ENABLE([mpi-size],
-              [AC_HELP_STRING([--enable-mpi-size],
-                              [Some systems (only SGI Altix Propack 4 so far) return wrong value
-                               from MPI_File_get_size.  By disabling this function, the library
-                               will replace it with stat to get the correct file size.
-                               [default=yes]])],
-              [MPI_GET_SIZE=$enableval])
-
-AC_MSG_CHECKING([if MPI_File_get_size is enabled])
-
-AC_SUBST(MPI_GET_SIZE)
-case "X-$MPI_GET_SIZE" in
-  X-no)
-    AC_MSG_RESULT([no])
-    MPI_GET_SIZE=no
-    ;;
-  X-yes|*)
-    AC_MSG_RESULT([yes])
-    MPI_GET_SIZE=yes
-    AC_DEFINE([HAVE_MPI_GET_SIZE], [1],
-              [Define if MPI_File_get_size works correctly])
-    ;;
-esac
-
-dnl ----------------------------------------------------------------------
-dnl Check to see whether the complicate MPI derived datatype works. 
-dnl In Dec. 20th, 2004, we found that IBM's MPIO implemention didn't
-dnl handle with the displacement of the complicate MPI type derived datatype 
-dnl correctly. So we add the check here.
-dnl IBM fixed this bug in their new version that supported MPI-IO around spring 2005. 
-dnl We find that mpich 1.2.5 has the similar bug. The same
-dnl bug also occurs at SGI IRIX 6.5 C with compiler version lower than or equal to 7.3.
-dnl In case people still use the old compiler, we keep this flag.
-AC_MSG_CHECKING([if irregular hyperslab optimization code works inside MPI-IO])
-
-AC_CACHE_VAL([hdf5_cv_mpi_complex_derived_datatype_works],[hdf5_cv_mpi_complex_derived_datatype_works=yes])
-
-if test ${hdf5_cv_mpi_complex_derived_datatype_works} = "yes"; then
-  AC_DEFINE([MPI_COMPLEX_DERIVED_DATATYPE_WORKS], [1],
-            [Define if your system can handle complicated MPI derived datatype correctly.])
-  AC_MSG_RESULT([yes])
-else
-  AC_MSG_RESULT([no])
-fi
-
-
-dnl ----------------------------------------------------------------------
-dnl Check to see whether MPI-IO can do collective IO successfully when one or more processes don't do 
-dnl any IOs.
-dnl Up to now(Feb. 8th, 2006), we find that it will cause program hung with mpich 1.2.x version 
-dnl and SGI altix. For those systems, we have to turn off this feature and use independent IO instead.
-dnl
-AC_MSG_CHECKING([if MPI-IO can do collective IO when one or more processes don't do IOs])
-
-AC_CACHE_VAL([hdf5_cv_mpi_special_collective_io_works],[hdf5_cv_mpi_special_collective_io_works=yes])
-
-if test ${hdf5_cv_mpi_special_collective_io_works} = "yes"; then
-  AC_DEFINE([MPI_SPECIAL_COLLECTIVE_IO_WORKS], [1],
-            [Define if your system can handle special collective IO properly.])
-  AC_MSG_RESULT([yes])
-else
-  AC_MSG_RESULT([no])
-fi
+  dnl ----------------------------------------------------------------------
+  dnl Set the flag to indicate that the MPI_File_get_size() function
+  dnl works.  The default is enabled unless the user knows the function
+  dnl doesn't work on the system and disables it.  (This flag should be set
+  dnl for all machines except for SGI Altix Propack 4 where the function 
+  dnl doesn't return correct file size.)
+  dnl
+  AC_ARG_ENABLE([mpi-size],
+                [AC_HELP_STRING([--enable-mpi-size],
+                                [Some systems (only SGI Altix Propack 4 so far) return wrong value
+                                 from MPI_File_get_size.  By disabling this function, the library
+                                 will replace it with stat to get the correct file size.
+                                 [default=yes]])],
+                [MPI_GET_SIZE=$enableval])
+
+  AC_MSG_CHECKING([if MPI_File_get_size is enabled])
+
+  AC_SUBST(MPI_GET_SIZE)
+  case "X-$MPI_GET_SIZE" in
+    X-no)
+      AC_MSG_RESULT([no])
+      MPI_GET_SIZE=no
+      ;;
+    X-yes|*)
+      AC_MSG_RESULT([yes])
+      MPI_GET_SIZE=yes
+      AC_DEFINE([HAVE_MPI_GET_SIZE], [1],
+                [Define if MPI_File_get_size works correctly])
+      ;;
+  esac
 fi
 
 dnl ----------------------------------------------------------------------
diff --git a/release_docs/RELEASE.txt b/release_docs/RELEASE.txt
index a8b0ba4..592113f 100644
--- a/release_docs/RELEASE.txt
+++ b/release_docs/RELEASE.txt
@@ -156,6 +156,12 @@ New Features
 
     Parallel Library:
     -----------------
+    - Special Collective IO (IO when some processes do not contribute to the
+      IO) and Complex Derived Datatype MPI functionalities are no longer
+      conditionally enabled in the library by configure. They are always
+      enabled in order to take advantage of performance boosts from these
+      behaviors. Older MPI implementations that do not allow for these
+      functionalities can no longer by used by HDF5. (MAM - 2011/07/08).
     - Modified parallel tests to run with arbitrary number of processes. The
       modified tests are testphdf5 (parallel dataset access), t_chunk_alloc 
       (chunk allocation), and t_posix_compliant (posix compliance). The rest of
diff --git a/src/H5Dmpio.c b/src/H5Dmpio.c
index e646a7b..1c69305 100644
--- a/src/H5Dmpio.c
+++ b/src/H5Dmpio.c
@@ -17,33 +17,33 @@
  * Programmer:  rky 980813
  * KY 2005 revised the code and made the change to support and optimize
  * collective IO support.
- * Purpose:	Functions to read/write directly between app buffer and file.
+ * Purpose:    Functions to read/write directly between app buffer and file.
  *
- * 		Beware of the ifdef'ed print statements.
- *		I didn't make them portable.
+ *         Beware of the ifdef'ed print statements.
+ *         I didn't make them portable.
  */
 
 /****************/
 /* Module Setup */
 /****************/
 
-#define H5D_PACKAGE		/*suppress error about including H5Dpkg	  */
+#define H5D_PACKAGE /* suppress error about including H5Dpkg */
 
 
 /***********/
 /* Headers */
 /***********/
-#include "H5private.h"		/* Generic Functions			*/
-#include "H5Dpkg.h"		/* Datasets				*/
-#include "H5Eprivate.h"		/* Error handling		  	*/
-#include "H5Fprivate.h"		/* File access				*/
-#include "H5FDprivate.h"	/* File drivers				*/
-#include "H5Iprivate.h"		/* IDs			  		*/
-#include "H5MMprivate.h"	/* Memory management			*/
-#include "H5Oprivate.h"		/* Object headers		  	*/
-#include "H5Pprivate.h"         /* Property lists                       */
-#include "H5Sprivate.h"		/* Dataspaces 				*/
-#include "H5Vprivate.h"         /* Vector                               */
+#include "H5private.h"        /* Generic Functions */
+#include "H5Dpkg.h"           /* Datasets          */
+#include "H5Eprivate.h"       /* Error handling    */
+#include "H5Fprivate.h"       /* File access       */
+#include "H5FDprivate.h"      /* File drivers      */
+#include "H5Iprivate.h"       /* IDs               */
+#include "H5MMprivate.h"      /* Memory management */
+#include "H5Oprivate.h"       /* Object headers    */
+#include "H5Pprivate.h"       /* Property lists    */
+#include "H5Sprivate.h"       /* Dataspaces        */
+#include "H5Vprivate.h"       /* Vector            */
 
 #ifdef H5_HAVE_PARALLEL
 
@@ -107,20 +107,16 @@ static herr_t H5D_multi_chunk_collective_io(H5D_io_info_t *io_info,
     H5P_genplist_t *dx_plist);
 static herr_t H5D_multi_chunk_collective_io_no_opt(H5D_io_info_t *io_info,
     const H5D_type_info_t *type_info, H5D_chunk_map_t *fm, H5P_genplist_t *dx_plist);
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
 static herr_t H5D_link_chunk_collective_io(H5D_io_info_t *io_info,
     const H5D_type_info_t *type_info, H5D_chunk_map_t *fm, int sum_chunk);
-#endif /* H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
 static herr_t H5D_inter_collective_io(H5D_io_info_t *io_info,
     const H5D_type_info_t *type_info, const H5S_t *file_space,
     const H5S_t *mem_space);
 static herr_t H5D_final_collective_io(H5D_io_info_t *io_info,
     const H5D_type_info_t *type_info, hsize_t nelmts, MPI_Datatype *mpi_file_type,
     MPI_Datatype *mpi_buf_type);
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
 static herr_t H5D_sort_chunk(H5D_io_info_t *io_info, const H5D_chunk_map_t *fm,
     H5D_chunk_addr_info_t chunk_addr_info_array[], int many_chunk_opt);
-#endif /* H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
 static herr_t H5D_obtain_mpio_mode(H5D_io_info_t *io_info, H5D_chunk_map_t *fm,
     H5P_genplist_t *dx_plist, uint8_t assign_io_mode[], haddr_t chunk_addr[]);
 static herr_t H5D_ioinfo_xfer_mode(H5D_io_info_t *io_info, H5P_genplist_t *dx_plist,
@@ -145,15 +141,15 @@ static herr_t H5D_mpio_get_sum_chunk(const H5D_io_info_t *io_info,
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_mpio_opt_possible
+ * Function:    H5D_mpio_opt_possible
  *
- * Purpose:	Checks if an direct I/O transfer is possible between memory and
+ * Purpose:     Checks if an direct I/O transfer is possible between memory and
  *                  the file.
  *
- * Return:	Success:        Non-negative: TRUE or FALSE
- *		Failure:	Negative
+ * Return:      Sauccess:   Non-negative: TRUE or FALSE
+ *              Failure:    Negative
  *
- * Programmer:	Quincey Koziol
+ * Programmer:  Quincey Koziol
  *              Wednesday, April 3, 2002
  *
  *-------------------------------------------------------------------------
@@ -225,19 +221,8 @@ H5D_mpio_opt_possible(const H5D_io_info_t *io_info, const H5S_t *file_space,
      *  storage.  For contiguous storage, mem_space and file_space won't change
      *  when it it is doing disk IO.  For chunking storage, mem_space will
      *  change for different chunks. So for chunking storage, whether we can
-     *  use collective IO will defer until each chunk IO is reached.  For
-     *  contiguous storage, if we find MPI-IO cannot support complicated MPI
-     *  derived data type and the shape of data space is not regular, we will
-     *  set use_par_opt_io = FALSE.
+     *  use collective IO will defer until each chunk IO is reached.
      */
-#ifndef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-    if(io_info->dset->shared->layout.type == H5D_CONTIGUOUS)
-        if((H5S_SELECT_IS_REGULAR(file_space) != TRUE) ||
-                (H5S_SELECT_IS_REGULAR(mem_space) != TRUE)) {
-            local_opinion = FALSE;
-            goto broadcast;
-        } /* end if */
-#endif
 
     /* Don't allow collective operations if filters need to be applied */
     if(io_info->dset->shared->layout.type == H5D_CHUNKED) {
@@ -245,24 +230,6 @@ H5D_mpio_opt_possible(const H5D_io_info_t *io_info, const H5S_t *file_space,
             local_opinion = FALSE;
             goto broadcast;
         } /* end if */
-
-/* If H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS and H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
- *      are defined, the HDF5 library will do collective IO if the application
- *      asks for it.
- *
- * If H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS is not defined and one or more
- *      processes are not participating in the IO, then collective IO is not
- *      assured. The library will check each process for the number of chunks
- *      it involves. If any process involves zero chunks, the library will use
- *      independent IO mode instead.
- */
-#ifndef H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS
-        /* Check the number of chunks to perform I/O on */
-        if(0 == H5SL_count(fm->sel_chunks)) {
-            local_opinion = FALSE;
-            goto broadcast;
-         } /* end if */
-#endif /* H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS */
     } /* end if */
 
 broadcast:
@@ -280,11 +247,11 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_mpio_select_read
+ * Function:    H5D_mpio_select_read
  *
- * Purpose:	MPI-IO function to read directly from app buffer to file.
+ * Purpose:     MPI-IO function to read directly from app buffer to file.
  *
- * Return:	non-negative on success, negative on failure.
+ * Return:      non-negative on success, negative on failure.
  *
  * Programmer:
  *
@@ -301,7 +268,7 @@ H5D_mpio_select_read(const H5D_io_info_t *io_info, const H5D_type_info_t UNUSED
 
     H5_CHECK_OVERFLOW(mpi_buf_count, hsize_t, size_t);
     if(H5F_block_read(io_info->dset->oloc.file, H5FD_MEM_DRAW, store_contig->dset_addr, (size_t)mpi_buf_count, io_info->dxpl_id, io_info->u.rbuf) < 0)
-	HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "can't finish collective parallel read")
+        HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "can't finish collective parallel read")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -309,11 +276,11 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_mpio_select_write
+ * Function:    H5D_mpio_select_write
  *
- * Purpose:	MPI-IO function to write directly from app buffer to file.
+ * Purpose:     MPI-IO function to write directly from app buffer to file.
  *
- * Return:	non-negative on success, negative on failure.
+ * Return:      non-negative on success, negative on failure.
  *
  * Programmer:
  *
@@ -339,14 +306,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_ioinfo_xfer_mode
+ * Function:    H5D_ioinfo_xfer_mode
  *
- * Purpose:	Switch to between collective & independent MPI I/O
+ * Purpose:     Switch to between collective & independent MPI I/O
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
- *		Friday, August 12, 2005
+ * Programmer:  Quincey Koziol
+ *              Friday, August 12, 2005
  *
  *-------------------------------------------------------------------------
  */
@@ -354,7 +321,7 @@ static herr_t
 H5D_ioinfo_xfer_mode(H5D_io_info_t *io_info, H5P_genplist_t *dx_plist,
     H5FD_mpio_xfer_t xfer_mode)
 {
-    herr_t	ret_value = SUCCEED;	/*return value		*/
+    herr_t  ret_value = SUCCEED;    /* return value */
 
     FUNC_ENTER_NOAPI_NOINIT(H5D_ioinfo_xfer_mode)
 
@@ -383,15 +350,15 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_ioinfo_coll_opt_mode
+ * Function:    H5D_ioinfo_coll_opt_mode
  *
- * Purpose:	Switch between using collective & independent MPI I/O w/file
+ * Purpose:     Switch between using collective & independent MPI I/O w/file
  *              set view
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	MuQun Yang
- *		Oct. 5th, 2006
+ * Programmer:  MuQun Yang
+ *              Oct. 5th, 2006
  *
  *-------------------------------------------------------------------------
  */
@@ -399,7 +366,7 @@ static herr_t
 H5D_ioinfo_coll_opt_mode(H5D_io_info_t *io_info, H5P_genplist_t *dx_plist,
     H5FD_mpio_collective_opt_t coll_opt_mode)
 {
-    herr_t	ret_value = SUCCEED;	/*return value		*/
+    herr_t  ret_value = SUCCEED;    /* return value */
 
     FUNC_ENTER_NOAPI_NOINIT(H5D_ioinfo_coll_opt_mode)
 
@@ -414,14 +381,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_mpio_get_min_chunk
+ * Function:    H5D_mpio_get_min_chunk
  *
- * Purpose:	Routine for obtaining minimum number of chunks to cover
+ * Purpose:     Routine for obtaining minimum number of chunks to cover
  *              hyperslab selection selected by all processors.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -449,14 +416,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_mpio_get_sum_chunk
+ * Function:    H5D_mpio_get_sum_chunk
  *
- * Purpose:	Routine for obtaining total number of chunks to cover
+ * Purpose:     Routine for obtaining total number of chunks to cover
  *              hyperslab selection selected by all processors.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -487,14 +454,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_contig_collective_read
+ * Function:    H5D_contig_collective_read
  *
- * Purpose:	Reads directly from contiguous data in file into application
+ * Purpose:     Reads directly from contiguous data in file into application
  *              memory using collective I/O.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
+ * Programmer:  Quincey Koziol
  *              Tuesday, March  4, 2008
  *
  *-------------------------------------------------------------------------
@@ -514,7 +481,7 @@ H5D_contig_collective_read(H5D_io_info_t *io_info, const H5D_type_info_t *type_i
 
     /* Call generic internal collective I/O routine */
     if(H5D_inter_collective_io(io_info, type_info, file_space, mem_space) < 0)
-	HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "couldn't finish shared collective MPI-IO")
+        HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "couldn't finish shared collective MPI-IO")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -522,14 +489,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_contig_collective_write
+ * Function:    H5D_contig_collective_write
  *
- * Purpose:	Write directly to contiguous data in file from application
+ * Purpose:     Write directly to contiguous data in file from application
  *              memory using collective I/O.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
+ * Programmer:  Quincey Koziol
  *              Tuesday, March  4, 2008
  *
  *-------------------------------------------------------------------------
@@ -549,7 +516,7 @@ H5D_contig_collective_write(H5D_io_info_t *io_info, const H5D_type_info_t *type_
 
     /* Call generic internal collective I/O routine */
     if(H5D_inter_collective_io(io_info, type_info, file_space, mem_space) < 0)
-	HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "couldn't finish shared collective MPI-IO")
+        HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "couldn't finish shared collective MPI-IO")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -557,9 +524,9 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_chunk_collective_io
+ * Function:    H5D_chunk_collective_io
  *
- * Purpose:	Routine for
+ * Purpose:     Routine for
  *              1) choose an IO option:
  *                    a) One collective IO defined by one MPI derived datatype to link through all chunks
  *              or    b) multiple chunk IOs,to do MPI-IO for each chunk, the IO mode may be adjusted
@@ -570,7 +537,7 @@ done:
  *                      3. Build up the final MPI derived datatype
  *                      4. Set up collective IO property list
  *                      5. Do IO
- *             For option b)
+ *              For option b)
  *                      1. Use MPI_gather and MPI_Bcast to obtain information of *collective/independent/none*
  *                         IO mode for each chunk of the selection
  *                      2. Depending on whether the IO mode is collective or independent or none,
@@ -579,9 +546,9 @@ done:
  *                      3. Set up collective IO property list for collective mode
  *                      4. DO IO
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -636,43 +603,9 @@ H5D_chunk_collective_io(H5D_io_info_t *io_info, const H5D_type_info_t *type_info
         else
             temp_not_link_io = TRUE;
 #endif
-   } /* end else */
-
-#ifndef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-    if(io_option == H5D_ONE_LINK_CHUNK_IO) {
-        io_option = H5D_MULTI_CHUNK_IO; /* We can not do this with one chunk IO. */
-#ifdef  H5_HAVE_INSTRUMENTED_LIBRARY
-    {  int new_value;
-       htri_t check_prop;
-       check_prop = H5Pexist(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_LINK_TO_MULTI);
-       if(check_prop > 0) {
-           new_value = 1;
-           if(H5Pset(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_LINK_TO_MULTI, &new_value) < 0)
-                HGOTO_ERROR(H5E_IO, H5E_CANTSET, FAIL, "unable to set property value")
-
-       }
-     }/* add this property because the library changes the option from one link to multiple chunks.*/
-#endif
-    }
-    if(io_option == H5D_ONE_LINK_CHUNK_IO_MORE_OPT){
-        io_option = H5D_MULTI_CHUNK_IO_MORE_OPT;
-#ifdef  H5_HAVE_INSTRUMENTED_LIBRARY
-      { int        new_value;
-       htri_t check_prop;
-       check_prop = H5Pexist(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_LINK_TO_MULTI_OPT);
-       if(check_prop > 0) {
-           new_value = 1;
-           if(H5Pset(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_LINK_TO_MULTI_OPT, &new_value) < 0)
-                HGOTO_ERROR(H5E_IO, H5E_CANTSET, FAIL, "unable to set property value")
-
-       }
-      }/* add this property because the library changes the option from one link to multiple chunks.*/
-#endif
-    }
-#endif
+    } /* end else */
 
 #ifdef H5_HAVE_INSTRUMENTED_LIBRARY
-{
     htri_t            check_prop;
     int               new_value;
 
@@ -709,17 +642,14 @@ H5D_chunk_collective_io(H5D_io_info_t *io_info, const H5D_type_info_t *type_info
                 HGOTO_ERROR(H5E_IO, H5E_CANTSET, FAIL, "unable to set property value")
         } /* end if */
     } /* end if */
-}
 #endif
 
     /* step 2:  Go ahead to do IO.*/
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
     if(io_option == H5D_ONE_LINK_CHUNK_IO || io_option == H5D_ONE_LINK_CHUNK_IO_MORE_OPT) {
         if(H5D_link_chunk_collective_io(io_info, type_info, fm, sum_chunk) < 0)
             HGOTO_ERROR(H5E_IO, H5E_CANTGET, FAIL, "couldn't finish linked chunk MPI-IO")
     } /* end if */
     else
-#endif /* H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
     if(io_option == H5D_MULTI_CHUNK_IO) {
         if(H5D_multi_chunk_collective_io_no_opt(io_info, type_info, fm, dx_plist) < 0)
             HGOTO_ERROR(H5E_IO, H5E_CANTGET, FAIL, "couldn't finish multiple chunk MPI-IO")
@@ -735,14 +665,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_chunk_collective_read
+ * Function:    H5D_chunk_collective_read
  *
- * Purpose:	Reads directly from chunks in file into application memory
+ * Purpose:     Reads directly from chunks in file into application memory
  *              using collective I/O.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
+ * Programmer:  Quincey Koziol
  *              Tuesday, March  4, 2008
  *
  *-------------------------------------------------------------------------
@@ -766,14 +696,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_chunk_collective_write
+ * Function:    H5D_chunk_collective_write
  *
- * Purpose:	Write directly to chunks in file from application memory
+ * Purpose:     Write directly to chunks in file from application memory
  *              using collective I/O.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Quincey Koziol
+ * Programmer:  Quincey Koziol
  *              Tuesday, March  4, 2008
  *
  *-------------------------------------------------------------------------
@@ -795,21 +725,20 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D_chunk_collective_write() */
 
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_link_chunk_collective_io
+ * Function:    H5D_link_chunk_collective_io
  *
- * Purpose:	Routine for one collective IO with one MPI derived datatype to link with all chunks
+ * Purpose:     Routine for one collective IO with one MPI derived datatype to link with all chunks
  *
  *                      1. Sort the chunk address and chunk info
  *                      2. Build up MPI derived datatype for each chunk
  *                      3. Build up the final MPI derived datatype
  *                      4. Use common collective IO routine to do MPI-IO
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -833,7 +762,7 @@ H5D_link_chunk_collective_io(H5D_io_info_t *io_info, const H5D_type_info_t *type
     hbool_t            *chunk_mft_is_derived_array = NULL;      /* Flags to indicate each chunk's MPI file datatype is derived */
     hbool_t            *chunk_mbt_is_derived_array = NULL;      /* Flags to indicate each chunk's MPI memory datatype is derived */
     int                *chunk_mpi_file_counts = NULL;   /* Count of MPI file datatype for each chunk */
-    int		       *chunk_mpi_mem_counts = NULL;    /* Count of MPI memory datatype for each chunk */
+    int                *chunk_mpi_mem_counts = NULL;    /* Count of MPI memory datatype for each chunk */
     int                 mpi_code;           /* MPI return code */
     herr_t              ret_value = SUCCEED;
 
@@ -871,21 +800,22 @@ H5D_link_chunk_collective_io(H5D_io_info_t *io_info, const H5D_type_info_t *type
 
         /* Check for this process having selection in this chunk */
         chunk_node = H5SL_first(fm->sel_chunks);
-	if(chunk_node == NULL) {
-            /* Set the dataspace info for I/O to NULL, this process doesn't have any I/O to perform */
-            fspace = mspace = NULL;
-	} /* end if */
-	else {
-            H5D_chunk_info_t *chunk_info;
-
-            /* Get the chunk info, for the selection in the chunk */
-            if(NULL == (chunk_info = H5SL_item(chunk_node)))
-                HGOTO_ERROR(H5E_STORAGE, H5E_CANTGET, FAIL, "couldn't get chunk info from skipped list")
 
-            /* Set the dataspace info for I/O */
-            fspace = chunk_info->fspace;
-            mspace = chunk_info->mspace;
-	} /* end else */
+        if(chunk_node == NULL) {
+                /* Set the dataspace info for I/O to NULL, this process doesn't have any I/O to perform */
+                fspace = mspace = NULL;
+        } /* end if */
+        else {
+                H5D_chunk_info_t *chunk_info;
+
+                /* Get the chunk info, for the selection in the chunk */
+                if(NULL == (chunk_info = H5SL_item(chunk_node)))
+                    HGOTO_ERROR(H5E_STORAGE, H5E_CANTGET, FAIL, "couldn't get chunk info from skipped list")
+
+                /* Set the dataspace info for I/O */
+                fspace = chunk_info->fspace;
+                mspace = chunk_info->mspace;
+        } /* end else */
 
         /* Set up the base storage address for this chunk */
         io_info->store = &ctg_store;
@@ -943,6 +873,7 @@ if(H5DEBUG(D))
             if(H5D_sort_chunk(io_info, fm, chunk_addr_info_array, sum_chunk) < 0)
                 HGOTO_ERROR(H5E_DATASPACE, H5E_CANTSWAP, FAIL, "unable to sort chunk address")
             ctg_store.contig.dset_addr = chunk_addr_info_array[0].chunk_addr;
+
 #ifdef H5D_DEBUG
 if(H5DEBUG(D))
     HDfprintf(H5DEBUG(D),"after sorting the chunk address \n");
@@ -1055,7 +986,7 @@ if(H5DEBUG(D))
     if(chunk_mpi_file_counts)
         H5MM_xfree(chunk_mpi_file_counts);
     if(chunk_mbt_is_derived_array)
-	H5MM_xfree(chunk_mbt_is_derived_array);
+        H5MM_xfree(chunk_mbt_is_derived_array);
     if(chunk_mft_is_derived_array)
         H5MM_xfree(chunk_mft_is_derived_array);
 
@@ -1067,22 +998,21 @@ if(H5DEBUG(D))
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D_link_chunk_collective_io */
-#endif /* H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_multi_chunk_collective_io
+ * Function:    H5D_multi_chunk_collective_io
  *
- * Purpose:	To do IO per chunk according to IO mode(collective/independent/none)
+ * Purpose:     To do IO per chunk according to IO mode(collective/independent/none)
  *
  *              1. Use MPI_gather and MPI_Bcast to obtain IO mode in each chunk(collective/independent/none)
  *              2. Depending on whether the IO mode is collective or independent or none,
  *                 Create either MPI derived datatype for each chunk or just do independent IO
  *              3. Use common collective IO routine to do MPI-IO
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -1169,7 +1099,7 @@ if(H5DEBUG(D))
             /* Pass in chunk's coordinates in a union. */
             store.chunk.offset  = chunk_info->coords;
             store.chunk.index   = chunk_info->index;
-	} /* end if */
+        } /* end if */
 
         /* Collective IO for this chunk,
          * Note: even there is no selection for this process, the process still
@@ -1185,10 +1115,10 @@ if(H5DEBUG(D))
             if(chunk_info) {
                 fspace = chunk_info->fspace;
                 mspace = chunk_info->mspace;
-	    } /* end if */
-	    else {
+            } /* end if */
+            else {
                 fspace = mspace = NULL;
-	    } /* end else */
+            } /* end else */
 
             /* Switch back to collective I/O */
             if(last_xfer_mode != H5FD_MPIO_COLLECTIVE) {
@@ -1208,8 +1138,8 @@ if(H5DEBUG(D))
             /* Perform the I/O */
             if(H5D_inter_collective_io(&ctg_io_info, type_info, fspace, mspace) < 0)
                 HGOTO_ERROR(H5E_IO, H5E_CANTGET, FAIL, "couldn't finish shared collective MPI-IO")
-	} /* end if */
-	else {  /* possible independent IO for this chunk */
+        } /* end if */
+        else {  /* possible independent IO for this chunk */
 #ifdef H5D_DEBUG
 if(H5DEBUG(D))
     HDfprintf(H5DEBUG(D),"inside independent IO mpi_rank = %d, chunk index = %Zu\n", mpi_rank, u);
@@ -1217,81 +1147,6 @@ if(H5DEBUG(D))
 
             HDassert(chunk_io_option[u] == 0);
 
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-            /* Check if this process has something to do with this chunk */
-            if(chunk_info) {
-                H5D_io_info_t *chk_io_info;     /* Pointer to I/O info object for this chunk */
-                H5D_chunk_ud_t udata;         /* B-tree pass-through	*/
-                void *chunk;                    /* Pointer to the data chunk in cache */
-                uint32_t accessed_bytes;          /* Total accessed size in a chunk */
-                htri_t cacheable;               /* Whether the chunk is cacheable */
-
-                /* Switch to independent I/O */
-                if(last_xfer_mode != H5FD_MPIO_INDEPENDENT) {
-                    if(H5D_ioinfo_xfer_mode(io_info, dx_plist, H5FD_MPIO_INDEPENDENT) < 0)
-                        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't switch to independent I/O")
-                    last_xfer_mode = H5FD_MPIO_INDEPENDENT;
-                } /* end if */
-
-                /* Load the chunk into cache.  But if the whole chunk is written,
-                 * simply allocate space instead of load the chunk.
-                 */
-                if(H5D_chunk_lookup(io_info->dset, io_info->dxpl_id,
-                        chunk_info->coords, chunk_info->index, &udata) < 0)
-                    HGOTO_ERROR(H5E_STORAGE, H5E_CANTGET, FAIL, "couldn't get chunk info from skipped list")
-
-                /* Load the chunk into cache and lock it. */
-                if((cacheable = H5D_chunk_cacheable(io_info, udata.addr,
-                        io_info->op_type == H5D_IO_OP_WRITE)) < 0)
-                    HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't tell if chunk is cacheable")
-                if(cacheable) {
-                    hbool_t entire_chunk = TRUE;         /* Whether whole chunk is selected */
-
-                    /* Compute # of bytes accessed in chunk */
-                    accessed_bytes = chunk_info->chunk_points * type_info->src_type_size;
-
-                    /* Determine if we will access all the data in the chunk */
-                    if(((io_info->op_type == H5D_IO_OP_WRITE) && (accessed_bytes != ctg_store.contig.dset_size))
-                            || (io_info->op_type != H5D_IO_OP_WRITE))
-                        entire_chunk = FALSE;
-
-                    /* Lock the chunk into the cache */
-                    if(NULL == (chunk = H5D_chunk_lock(io_info, &udata, entire_chunk)))
-                        HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "unable to read raw data chunk")
-
-                    /* Set up the storage buffer information for this chunk */
-                    cpt_store.compact.buf = chunk;
-
-                    /* Point I/O info at contiguous I/O info for this chunk */
-                    chk_io_info = &cpt_io_info;
-                } /* end if */
-                else {
-                    /* Set up the storage address information for this chunk */
-                    ctg_store.contig.dset_addr = udata.addr;
-
-                    /* No chunk cached */
-                    chunk = NULL;
-
-                    /* Point I/O info at temporary I/O info for this chunk */
-                    chk_io_info = &ctg_io_info;
-                } /* end else */
-
-                if(io_info->op_type == H5D_IO_OP_WRITE) {
-                    if((io_info->io_ops.single_write)(chk_io_info, type_info,
-                            (hsize_t)chunk_info->chunk_points, chunk_info->fspace, chunk_info->mspace) < 0)
-                        HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "optimized write failed")
-                } /* end if */
-                else {
-                    if((io_info->io_ops.single_read)(chk_io_info, type_info,
-                            (hsize_t)chunk_info->chunk_points, chunk_info->fspace, chunk_info->mspace) < 0)
-                        HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "optimized read failed")
-                } /* end else */
-
-                /* Release the cache lock on the chunk. */
-                if(chunk && H5D_chunk_unlock(io_info, &udata, (io_info->op_type == H5D_IO_OP_WRITE), chunk, accessed_bytes) < 0)
-                    HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "unable to unlock raw data chunk")
-            } /* end if */
-#else /* !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS) */
             /* Set the file & memory dataspaces */
             if(chunk_info) {
                 fspace = chunk_info->fspace;
@@ -1318,7 +1173,6 @@ if(H5DEBUG(D))
   if(H5DEBUG(D))
     HDfprintf(H5DEBUG(D),"after inter collective IO\n");
 #endif
-#endif /* !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS) */
         } /* end else */
     } /* end for */
 
@@ -1333,9 +1187,9 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_multi_chunk_collective_io_no_opt
+ * Function:    H5D_multi_chunk_collective_io_no_opt
  *
- * Purpose:	To do collective IO without any optimization per chunk base
+ * Purpose:     To do collective IO without any optimization per chunk base
  *              The internal independent IO inside HDF5 cannot handle
  *              non-contiguous(or with holes) storage efficiently.
  *              Under this case, the one independent IO call may consist of
@@ -1352,9 +1206,9 @@ done:
  *              The HDF5 library won't do any IO management but leave it to MPI-IO to figure
  *              out.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -1416,7 +1270,7 @@ if(H5DEBUG(D)) {
      /* Iterate through chunks to be operated on */
     while(chunk_node) {
         H5D_chunk_info_t *chunk_info;   /* chunk information */
-        H5D_chunk_ud_t udata;		/* B-tree pass-through	*/
+        H5D_chunk_ud_t udata;           /* B-tree pass-through */
         hbool_t make_ind, make_coll;    /* Flags to indicate that the MPI mode should change */
 
         /* Get the actual chunk information from the skip list node */
@@ -1437,20 +1291,6 @@ if(H5DEBUG(D)) {
         if(count_chunk > min_chunk)
             /* Switch to independent I/O (permanently) */
             make_ind = TRUE;
-#ifndef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-/* This case needs to be improved to check if the selected space
-   is regular. If all selections are regular, collective IO can still be done.
-   However, since we find an MPI-IO bug at a DOE machine(mcr) that cannot
-   handle collective I/O selection for this case correctly,
-   we turn off this optimization but leave the following code
-   for future optimization. Otherwise, the following else {} doesn't make sense.
-   KY 2006/8/4/ */
-        else {
-            /* Switch to independent I/O (temporarily) */
-            make_ind = TRUE;
-            make_coll = TRUE;
-        } /* end else */
-#endif /* H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
 
         /* Retrieve the chunk's address */
         if(H5D_chunk_lookup(io_info->dset, io_info->dxpl_id, chunk_info->coords,
@@ -1542,14 +1382,14 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_inter_collective_io
+ * Function:    H5D_inter_collective_io
  *
- * Purpose:	Routine for the shared part of collective IO between multiple chunk
+ * Purpose:     Routine for the shared part of collective IO between multiple chunk
  *              collective IO and contiguous collective IO
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -1611,13 +1451,13 @@ if(H5DEBUG(D))
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_final_collective_io
+ * Function:    H5D_final_collective_io
  *
- * Purpose:	Routine for the common part of collective IO with different storages.
+ * Purpose:     Routine for the common part of collective IO with different storages.
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -1626,7 +1466,7 @@ static herr_t
 H5D_final_collective_io(H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
     hsize_t mpi_buf_count, MPI_Datatype *mpi_file_type, MPI_Datatype *mpi_buf_type)
 {
-    hbool_t	plist_is_setup = FALSE; /* Whether the dxpl has been customized */
+    hbool_t     plist_is_setup = FALSE; /* Whether the dxpl has been customized */
     herr_t      ret_value = SUCCEED;
 
     FUNC_ENTER_NOAPI_NOINIT(H5D_final_collective_io)
@@ -1638,7 +1478,7 @@ H5D_final_collective_io(H5D_io_info_t *io_info, const H5D_type_info_t *type_info
 
     if(io_info->op_type == H5D_IO_OP_WRITE) {
         if((io_info->io_ops.single_write)(io_info, type_info, mpi_buf_count, NULL, NULL) < 0)
-	    HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "optimized write failed")
+            HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "optimized write failed")
     } /* end if */
     else {
         if((io_info->io_ops.single_read)(io_info, type_info, mpi_buf_count, NULL, NULL) < 0)
@@ -1658,12 +1498,11 @@ if(H5DEBUG(D))
       FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D_final_collective_io */
 
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_sort_chunk
+ * Function:    H5D_sort_chunk
  *
- * Purpose:	Routine to sort chunks in increasing order of chunk address
+ * Purpose:     Routine to sort chunks in increasing order of chunk address
  *              Each chunk address is also obtained.
  *
  * Description:
@@ -1678,9 +1517,9 @@ if(H5DEBUG(D))
  *                     many_chunk_opt                         : flag to optimize the way to obtain chunk addresses
  *                                                              for many chunks
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -1699,7 +1538,7 @@ H5D_sort_chunk(H5D_io_info_t *io_info, const H5D_chunk_map_t *fm,
     int             mpi_size;                   /* Number of MPI processes */
     int             mpi_code;                   /* MPI return code */
     int             i;                          /* Local index variable */
-    herr_t	    ret_value = SUCCEED;        /* Return value		*/
+    herr_t          ret_value = SUCCEED;        /* Return value */
 
     FUNC_ENTER_NOAPI_NOINIT(H5D_sort_chunk)
 
@@ -1740,14 +1579,15 @@ if(H5DEBUG(D))
         /* Retrieve all the chunk addresses with process 0 */
         if((mpi_rank = H5F_mpi_get_rank(io_info->dset->oloc.file)) < 0)
             HGOTO_ERROR(H5E_IO, H5E_MPI, FAIL, "unable to obtain mpi rank")
-	if(mpi_rank == 0) {
+
+        if(mpi_rank == 0) {
             if(H5D_chunk_addrmap(io_info, total_chunk_addr_array) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
-	} /* end if */
+        } /* end if */
 
-	/* Broadcasting the MPI_IO option info. and chunk address info. */
-	if(MPI_SUCCESS != (mpi_code = MPI_Bcast(total_chunk_addr_array, (int)(sizeof(haddr_t) * fm->layout->u.chunk.nchunks), MPI_BYTE, (int)0, io_info->comm)))
-	   HMPI_GOTO_ERROR(FAIL, "MPI_BCast failed", mpi_code)
+        /* Broadcasting the MPI_IO option info. and chunk address info. */
+        if(MPI_SUCCESS != (mpi_code = MPI_Bcast(total_chunk_addr_array, (int)(sizeof(haddr_t) * fm->layout->u.chunk.nchunks), MPI_BYTE, (int)0, io_info->comm)))
+           HMPI_GOTO_ERROR(FAIL, "MPI_BCast failed", mpi_code)
     } /* end if */
 
     /* Start at first node in chunk skip list */
@@ -1801,13 +1641,12 @@ done:
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D_sort_chunk() */
-#endif /* H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5D_obtain_mpio_mode
+ * Function:    H5D_obtain_mpio_mode
  *
- * Purpose:	Routine to obtain each io mode(collective,independent or none) for each chunk;
+ * Purpose:     Routine to obtain each io mode(collective,independent or none) for each chunk;
  *              Each chunk address is also obtained.
  *
  * Description:
@@ -1833,9 +1672,9 @@ done:
  *              Output: uint8_t assign_io_mode[], : IO mode, collective, independent or none
  *                      haddr_t chunk_addr[],     : chunk address array for each chunk
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:      Non-negative on success/Negative on failure
  *
- * Programmer:	Muqun Yang
+ * Programmer:  Muqun Yang
  *              Monday, Feb. 13th, 2006
  *
  *-------------------------------------------------------------------------
@@ -1846,9 +1685,7 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
 {
     int               total_chunks;
     unsigned          percent_nproc_per_chunk, threshold_nproc_per_chunk;
-#if defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) && defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
     H5FD_mpio_chunk_opt_t chunk_opt_mode;
-#endif
     uint8_t*          io_mode_info = NULL;
     uint8_t*          recv_io_mode_info = NULL;
     uint8_t*          mergebuf = NULL;
@@ -1881,7 +1718,6 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
     /* Setup parameters */
     H5_ASSIGN_OVERFLOW(total_chunks, fm->layout->u.chunk.nchunks, hsize_t, int);
     percent_nproc_per_chunk = H5P_peek_unsigned(dx_plist, H5D_XFER_MPIO_CHUNK_OPT_RATIO_NAME);
-#if defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) && defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
     chunk_opt_mode = (H5FD_mpio_chunk_opt_t)H5P_peek_unsigned(dx_plist, H5D_XFER_MPIO_CHUNK_OPT_HARD_NAME);
     if((chunk_opt_mode == H5FD_MPIO_CHUNK_MULTI_IO) || (percent_nproc_per_chunk == 0)) {
         if(H5D_chunk_addrmap(io_info, chunk_addr) < 0)
@@ -1891,7 +1727,6 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
 
         HGOTO_DONE(SUCCEED)
     } /* end if */
-#endif
     threshold_nproc_per_chunk = mpi_size * percent_nproc_per_chunk/100;
 
     /* Allocate memory */
@@ -1907,16 +1742,7 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
     while(chunk_node) {
         chunk_info    = H5SL_item(chunk_node);
 
-#ifndef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-        /* regularity information: 1, selection information: 2 */
-        if(H5S_SELECT_IS_REGULAR(chunk_info->fspace) == TRUE &&
-                H5S_SELECT_IS_REGULAR(chunk_info->mspace) == TRUE)
-#endif
-            io_mode_info[chunk_info->index] = H5D_CHUNK_SELECT_REG; /* this chunk is selected and is "regular" without defining H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS. */
-#ifndef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-        else
-            io_mode_info[chunk_info->index] = H5D_CHUNK_SELECT_IRREG; /* this chunk is selected and is irregular*/
-#endif
+            io_mode_info[chunk_info->index] = H5D_CHUNK_SELECT_REG; /* this chunk is selected and is "regular" */
         chunk_node = H5SL_next(chunk_node);
     } /* end while */
 
@@ -1928,23 +1754,14 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
     if(mpi_rank == root) {
         int               nproc;
         int*              nproc_per_chunk;
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-        int*              ind_this_chunk;
-#endif
 
         /* pre-computing: calculate number of processes and
             regularity of the selection occupied in each chunk */
         nproc_per_chunk = (int*)H5MM_calloc(total_chunks * sizeof(int));
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-        ind_this_chunk   = (int*)H5MM_calloc(total_chunks * sizeof(int));
-#endif
 
         /* calculating the chunk address */
         if(H5D_chunk_addrmap(io_info, chunk_addr) < 0) {
             HDfree(nproc_per_chunk);
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-            HDfree(ind_this_chunk);
-#endif
             HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
         } /* end if */
 
@@ -1956,29 +1773,14 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
             for(ic = 0; ic < total_chunks; ic++, tmp_recv_io_mode_info++) {
                 if(*tmp_recv_io_mode_info != 0) {
                     nproc_per_chunk[ic]++;
-#ifndef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-                    if(*tmp_recv_io_mode_info == H5D_CHUNK_SELECT_IRREG)
-                        ind_this_chunk[ic] = 1;
-#endif
                 } /* end if */
-#ifndef H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS
-                else {
-                    /*checking whether we have a selection in this chunk */
-                    ind_this_chunk[ic] = 1;
-                } /* end else */
-#endif
             } /* end for */
         } /* end for */
 
         /* Calculating MPIO mode for each chunk (collective, independent, none) */
         for(ic = 0; ic < total_chunks; ic++) {
             if(nproc_per_chunk[ic] > MAX(1, threshold_nproc_per_chunk)) {
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-                if(!ind_this_chunk[ic])
-                    assign_io_mode[ic] = H5D_CHUNK_IO_MODE_COL;
-#else
                 assign_io_mode[ic] = H5D_CHUNK_IO_MODE_COL;
-#endif
             } /* end if */
         } /* end for */
 
@@ -1988,9 +1790,6 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
         HDmemcpy(tempbuf, chunk_addr, sizeof(haddr_t) * total_chunks);
 
         HDfree(nproc_per_chunk);
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-        HDfree(ind_this_chunk);
-#endif
     } /* end if */
 
     /* Broadcasting the MPI_IO option info. and chunk address info. */
@@ -2003,11 +1802,6 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
 #ifdef H5_HAVE_INSTRUMENTED_LIBRARY
     check_prop = H5Pexist(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_MULTI_RATIO_COLL_NAME);
     if(check_prop > 0) {
-#if !defined(H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS) || !defined(H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS)
-        new_value = 0;
-        if(H5Pset(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_MULTI_RATIO_COLL_NAME, &new_value) < 0)
-            HGOTO_ERROR(H5E_PLIST, H5E_UNSUPPORTED, FAIL, "unable to set property value")
-#else
         for(ic = 0; ic < total_chunks; ic++) {
             if(assign_io_mode[ic] == H5D_CHUNK_IO_MODE_COL) {
                 new_value = 0;
@@ -2016,7 +1810,6 @@ H5D_obtain_mpio_mode(H5D_io_info_t* io_info, H5D_chunk_map_t *fm,
                 break;
             } /* end if */
         } /* end for */
-#endif
     } /* end if */
 
     check_prop = H5Pexist(io_info->dxpl_id, H5D_XFER_COLL_CHUNK_MULTI_RATIO_IND_NAME);
diff --git a/src/H5config.h.in b/src/H5config.h.in
index 628996a..487ac1d 100644
--- a/src/H5config.h.in
+++ b/src/H5config.h.in
@@ -464,17 +464,10 @@
 /* Define if the metadata trace file code is to be compiled in */
 #undef METADATA_TRACE_FILE
 
-/* Define if your system can handle complicated MPI derived datatype
-   correctly. */
-#undef MPI_COMPLEX_DERIVED_DATATYPE_WORKS
-
 /* Define if your system's `MPI_File_set_size' function works for files over
    2GB. */
 #undef MPI_FILE_SET_SIZE_BIG
 
-/* Define if your system can handle special collective IO properly. */
-#undef MPI_SPECIAL_COLLECTIVE_IO_WORKS
-
 /* Define if we can violate pointer alignment restrictions */
 #undef NO_ALIGNMENT_RESTRICTIONS
 
diff --git a/testpar/t_mpi.c b/testpar/t_mpi.c
index c3e04de..cf2cb35 100644
--- a/testpar/t_mpi.c
+++ b/testpar/t_mpi.c
@@ -843,33 +843,13 @@ static int test_mpio_derived_dtype(char *filename) {
 
 
     mpi_err = MPI_Barrier(MPI_COMM_WORLD);
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
     if(retcode == -1) {
 	if(mpi_rank == 0) {
 	    printf("Complicated derived datatype is NOT working at this platform\n");
-	    printf("Go back to hdf5/config and find the corresponding\n");
-	    printf("configure-specific file (for example, powerpc-ibm-aix5.x) and add\n");
-	    printf("hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype-works='no'}\n");
-	    printf(" at the end of the file.\n");
-	    printf(" Please report to hdfhelp@ncsa.uiuc.edu about this problem.\n");
+	    printf(" Please report to help@hdfgroup.org about this problem.\n");
 	}
 	retcode = 1;
     }
-#else
-    if(retcode == 0) {
-	if(mpi_rank == 0) {
-	    printf(" This is NOT an error, What it really says is\n");
-	    printf("Complicated derived datatype is WORKING at this platform\n");
-	    printf(" Go back to hdf5/config and find the corresponding \n");
-	    printf(" configure-specific file (for example, powerpc-ibm-aix5.x) and delete the line\n");
-	    printf("hdf5_cv_mpi_complex_derived_datatype_works=${hdf5_cv_mpi_complex_derived_datatype-works='no'}\n");
-	    printf(" at the end of the file.\n");
-	    printf("Please report to hdfhelp@ncsa.uiuc.edu about this problem.\n");
-	}
-	retcode = 1;
-    }
-    if(retcode == -1) retcode = 0;
-#endif
     return retcode;
 }
 /*
@@ -907,30 +887,29 @@ test_mpio_special_collective(char *filename)
     char mpi_err_str[MPI_MAX_ERROR_STRING];
     int  mpi_err_strlen;
     int  mpi_err;
-    char writedata[2];
-    char *buf;
+    char writedata[2*DIMSIZE];
+    char filerep[7] = "native";
     int  i;
     int  count,bufcount;
     int blocklens[2];
     MPI_Aint offsets[2];
-    MPI_Offset  mpi_off;
+    MPI_Offset  mpi_off = 0;
     MPI_Status  mpi_stat;
-    int  retcode;
+    int  retcode = 0;
 
     MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);
     MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
-    retcode = 0;
 
     /* create MPI data type */
     etype = MPI_BYTE;
     if(mpi_rank == 0 || mpi_rank == 1) {
         count = DIMSIZE;
         bufcount = 1;
-    }
+    } /* end if */
     else {
         count = 0;
         bufcount = 0;
-    }
+    } /* end else */
 
     blocklens[0] = count;
     offsets[0] = mpi_rank*count;
@@ -938,108 +917,103 @@ test_mpio_special_collective(char *filename)
     offsets[1] = (mpi_size+mpi_rank)*count;
 
     if(count !=0) {
-      if((mpi_err= MPI_Type_hindexed(2,blocklens,offsets,etype,&filetype))
-       != MPI_SUCCESS){
-      	MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_Type_contiguous failed (%s)\n", mpi_err_str);
-	return 1;
-      }
-
-      if((mpi_err=MPI_Type_commit(&filetype))!=MPI_SUCCESS){
-        MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_Type_commit failed (%s)\n", mpi_err_str);
-	return 1;
-      }
-
-
-      if((mpi_err= MPI_Type_hindexed(2,blocklens,offsets,etype,&buftype))
-       != MPI_SUCCESS){
-      	MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_Type_contiguous failed (%s)\n", mpi_err_str);
-	return 1;
-      }
-
-      if((mpi_err=MPI_Type_commit(&buftype))!=MPI_SUCCESS){
+        if((mpi_err = MPI_Type_hindexed(2,
+                                        blocklens,
+                                        offsets,
+                                        etype,
+                                        &filetype)) != MPI_SUCCESS) {
+            MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+            printf("MPI_Type_contiguous failed (%s)\n", mpi_err_str);
+            return 1;
+        } /* end if */
+
+        if((mpi_err = MPI_Type_commit(&filetype)) != MPI_SUCCESS) {
+            MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+            printf("MPI_Type_commit failed (%s)\n", mpi_err_str);
+            return 1;
+        } /* end if */
+
+        if((mpi_err = MPI_Type_hindexed(2,
+                                        blocklens,
+                                        offsets,
+                                        etype,
+                                        &buftype)) != MPI_SUCCESS) {
+            MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+            printf("MPI_Type_contiguous failed (%s)\n", mpi_err_str);
+            return 1;
+        } /* end if */
+
+        if((mpi_err = MPI_Type_commit(&buftype)) != MPI_SUCCESS) {
+            MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+            printf("MPI_Type_commit failed (%s)\n", mpi_err_str);
+            return 1;
+        } /* end if */
+    } /* end if */
+    else {
+        filetype = MPI_BYTE;
+        buftype  = MPI_BYTE;
+    } /* end else */
+
+    /* Open a file */
+    if ((mpi_err = MPI_File_open(MPI_COMM_WORLD,
+                                 filename,
+                                 MPI_MODE_RDWR | MPI_MODE_CREATE,
+                                 MPI_INFO_NULL,
+                                 &fh)) != MPI_SUCCESS) {
         MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_Type_commit failed (%s)\n", mpi_err_str);
-	return 1;
-      }
-     }
-     else {
-
-       filetype = MPI_BYTE;
-       buftype  = MPI_BYTE;
-     }
-
-   /* Open a file */
-    if ((mpi_err = MPI_File_open(MPI_COMM_WORLD, filename,
-	    MPI_MODE_RDWR | MPI_MODE_CREATE ,
-	    MPI_INFO_NULL, &fh))
-	    != MPI_SUCCESS){
-	MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_File_open failed (%s)\n", mpi_err_str);
-	return 1;
-    }
+        printf("MPI_File_open failed (%s)\n", mpi_err_str);
+        return 1;
+    } /* end if */
 
     /* each process writes some data */
     for (i=0; i < 2*DIMSIZE; i++)
-	writedata[i] = mpi_rank*DIMSIZE + i;
-
-
-     mpi_off = 0;
-    if((mpi_err = MPI_File_set_view(fh, mpi_off, MPI_BYTE, filetype, "native", MPI_INFO_NULL))
-        != MPI_SUCCESS) {
-	MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_File_set_view failed (%s)\n", mpi_err_str);
-	return 1;
-    }
-
-    buf   = writedata;
-    if ((mpi_err = MPI_File_write_at_all(fh, mpi_off, buf, bufcount, buftype,
-	    &mpi_stat))
-	    != MPI_SUCCESS){
-	MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_File_write_at offset(%ld), bytes (%d), failed (%s)\n",
-		(long) mpi_off, bufcount, mpi_err_str);
-	return 1;
-    };
+        writedata[i] = (char)(mpi_rank*DIMSIZE + i);
+
+    /* Set the file view */
+    if((mpi_err = MPI_File_set_view(fh,
+                                    mpi_off,
+                                    MPI_BYTE,
+                                    filetype,
+                                    filerep,
+                                    MPI_INFO_NULL)) != MPI_SUCCESS) {
+        MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+        printf("MPI_File_set_view failed (%s)\n", mpi_err_str);
+        return 1;
+    } /* end if */
+
+    /* Collectively write into the file */
+    if ((mpi_err = MPI_File_write_at_all(fh,
+                                         mpi_off,
+                                         writedata,
+                                         bufcount,
+                                         buftype,
+                                         &mpi_stat)) != MPI_SUCCESS) {
+        MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+        printf("MPI_File_write_at offset(%ld), bytes (%d), failed (%s)\n",
+               (long) mpi_off, bufcount, mpi_err_str);
+        return 1;
+    } /* end if */
 
-     if ((mpi_err = MPI_File_close(&fh))
-	    != MPI_SUCCESS){
-	MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
-	printf("MPI_File_close failed. \n");
-	return 1;
-    };
+    /* Close the file */
+    if ((mpi_err = MPI_File_close(&fh)) != MPI_SUCCESS) {
+        MPI_Error_string(mpi_err, mpi_err_str, &mpi_err_strlen);
+        printf("MPI_File_close failed. \n");
+        return 1;
+    } /* end if */
 
+    /* Perform a barrier */
     mpi_err = MPI_Barrier(MPI_COMM_WORLD);
-#ifdef H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS
     if(retcode != 0) {
-	if(mpi_rank == 0) {
-	    printf("special collective IO is NOT working at this platform\n");
-	    printf("Go back to hdf5/config and find the corresponding\n");
-	    printf("configure-specific file (for example, powerpc-ibm-aix5.x) and add\n");
-	    printf("hdf5_cv_mpi_special_collective_io_works=${hdf5_cv_mpi_special_collective_io_works='no'}\n");
-	    printf(" at the end of the file.\n");
-	    printf(" Please report to hdfhelp@ncsa.uiuc.edu about this problem.\n");
-	}
-	retcode = 1;
-    }
-#else
-    if(retcode == 0) {
-	if(mpi_rank == 0) {
-	    printf(" This is NOT an error, What it really says is\n");
-	    printf("special collective IO is WORKING at this platform\n");
-	    printf(" Go back to hdf5/config and find the corresponding \n");
-	    printf(" configure-specific file (for example, powerpc-ibm-aix5.x) and delete the line\n");
-	    printf("hdf5_cv_mpi_special_collective_io_works=${hdf5_cv_mpi_special_collective_io_works='no'}\n");
-	    printf(" at the end of the file.\n");
-	    printf("Please report to hdfhelp@ncsa.uiuc.edu about this problem.\n");
-	}
-	retcode = 1;
-    }
-#endif
+        if(mpi_rank == 0) {
+            printf("special collective IO is NOT working at this platform\n");
+            printf(" Please report to help@hdfgroup.org about this problem.\n");
+        } /* end if */
+        retcode = 1;
+    } /* end if */
+
     return retcode;
-}
+
+} /* test_mpio_special_collective */
 
 /*
  * parse the command line options
@@ -1226,22 +1200,8 @@ main(int argc, char **argv)
     /*=======================================
      * MPIO complicated derived datatype test
      *=======================================*/
-    /* test_mpio_derived_dtype often hangs when fails.
-     * Do not run it if it is known NOT working unless ask to
-     * run explicitly by high verbose mode.
-     */
-#ifdef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS
     MPI_BANNER("MPIO complicated derived datatype test...");
     ret_code = test_mpio_derived_dtype(filenames[0]);
-#else
-    if (VERBOSE_HI){
-	MPI_BANNER("MPIO complicated derived datatype test...");
-	ret_code = test_mpio_derived_dtype(filenames[0]);
-    }else{
-	MPI_BANNER("MPIO complicated derived datatype test SKIPPED.");
-	ret_code = 0;	/* fake ret_code */
-    }
-#endif
     ret_code = errors_sum(ret_code);
     if (mpi_rank==0 && ret_code > 0){
 	printf("***FAILED with %d total errors\n", ret_code);
@@ -1251,34 +1211,17 @@ main(int argc, char **argv)
     /*=======================================
      * MPIO special collective IO  test
      *=======================================*/
-    /* test_special_collective_io  often hangs when fails.
-     * Do not run it if it is known NOT working unless ask to
-     * run explicitly by high verbose mode.
-     */
-    if(mpi_size !=4){
-      MPI_BANNER("MPIO special collective io test SKIPPED.");
-      if(mpi_rank == 0){
-        printf("Use FOUR processes to run this test\n");
-        printf("If you still see the <test SKIPPED>, use <-vh> option to verify the test\n");
-  }
-      ret_code = 0;
-      goto sc_finish;
-    }
+    if (mpi_size < 4) {
+        MPI_BANNER("MPIO special collective io test SKIPPED.");
+        if (mpi_rank == 0)
+            printf("This test needs at least four processes to run.\n");
+        ret_code = 0;
+        goto sc_finish;
+    } /* end if */
 
-#ifdef H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS
     MPI_BANNER("MPIO special collective io test...");
     ret_code = test_mpio_special_collective(filenames[0]);
 
-#else
-    if (VERBOSE_HI){
-	MPI_BANNER("MPIO special collective io test...");
-	ret_code = test_mpio_special_collective(filenames[0]);
-    }else{
-	MPI_BANNER("MPIO special collective io test SKIPPED.");
-	ret_code = 0;	/* fake ret_code */
-    }
-#endif
-
 sc_finish:
     ret_code = errors_sum(ret_code);
     if (mpi_rank==0 && ret_code > 0){
diff --git a/tools/h5diff/Makefile.in b/tools/h5diff/Makefile.in
index 196f2cd..02011a7 100644
--- a/tools/h5diff/Makefile.in
+++ b/tools/h5diff/Makefile.in
@@ -403,8 +403,8 @@ TRACE = perl $(top_srcdir)/bin/trace
 
 # Temporary files.  *.h5 are generated by h5diff.  They should
 # be copied to the testfiles/ directory if update is required
-CHECK_CLEANFILES = *.chkexe *.chklog *.clog *.h5 testfiles expect_sorted \
-	actual_sorted
+CHECK_CLEANFILES = *.chkexe *.chklog *.clog *.h5 testfiles \
+	expect_sorted actual_sorted
 
 # Include src and tools/lib directories
 INCLUDES = -I$(top_srcdir)/src -I$(top_srcdir)/tools/lib
diff --git a/vms/src/h5pubconf.h b/vms/src/h5pubconf.h
index 69b5ef8..f5718f0 100644
--- a/vms/src/h5pubconf.h
+++ b/vms/src/h5pubconf.h
@@ -456,17 +456,10 @@
 /* Define if the metadata trace file code is to be compiled in */
 /* #undef H5_METADATA_TRACE_FILE */
 
-/* Define if your system can handle complicated MPI derived datatype
-   correctly. */
-/* #undef H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS */
-
 /* Define if your system's `MPI_File_set_size' function works for files over
    2GB. */
 /* #undef H5_MPI_FILE_SET_SIZE_BIG */
 
-/* Define if your system can handle special collective IO properly. */
-/* #undef H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS */
-
 /* Define if we can violate pointer alignment restrictions */
 #define H5_NO_ALIGNMENT_RESTRICTIONS 1
 
diff --git a/windows/src/H5pubconf.h b/windows/src/H5pubconf.h
index 11ef5f6..2edd062 100755
--- a/windows/src/H5pubconf.h
+++ b/windows/src/H5pubconf.h
@@ -450,17 +450,10 @@
 /* Define if the metadata trace file code is to be compiled in */
 /* #undef H5_METADATA_TRACE_FILE */
 
-/* Define if your system can handle complicated MPI derived datatype
-   correctly. */
-#define H5_MPI_COMPLEX_DERIVED_DATATYPE_WORKS 1
-
 /* Define if your system's `MPI_File_set_size' function works for files over
    2GB. */
 #define H5_MPI_FILE_SET_SIZE_BIG 1
 
-/* Define if your system can handle special collective IO properly. */
-#define H5_MPI_SPECIAL_COLLECTIVE_IO_WORKS 1
-
 /* Define if we can violate pointer alignment restrictions */
 #define H5_NO_ALIGNMENT_RESTRICTIONS 1