Index: ompi/mca/coll/tuned/coll_tuned_allgatherv.c
===================================================================
--- ompi/mca/coll/tuned/coll_tuned_allgatherv.c	(revision 27511)
+++ ompi/mca/coll/tuned/coll_tuned_allgatherv.c	(working copy)
@@ -104,8 +104,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "coll:tuned:allgather_intra_bruck rank %d", rank));
    
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -230,8 +232,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "coll:tuned:allgatherv_intra_ring rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -373,8 +377,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "coll:tuned:allgatherv_intra_neighborexchange rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -507,8 +513,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "ompi_coll_tuned_allgatherv_intra_two_procs rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &lb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &lb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &lb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
Index: ompi/mca/coll/tuned/coll_tuned_allgather.c
===================================================================
--- ompi/mca/coll/tuned/coll_tuned_allgather.c	(revision 27511)
+++ ompi/mca/coll/tuned/coll_tuned_allgather.c	(working copy)
@@ -96,8 +96,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "coll:tuned:allgather_intra_bruck rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -288,8 +290,10 @@
                  "coll:tuned:allgather_intra_recursivedoubling rank %d, size %d", 
                  rank, size));
 
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -376,8 +380,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "coll:tuned:allgather_intra_ring rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -514,8 +520,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "coll:tuned:allgather_intra_neighborexchange rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &slb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &slb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &rlb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
@@ -619,8 +627,10 @@
     OPAL_OUTPUT((ompi_coll_tuned_stream,
                  "ompi_coll_tuned_allgather_intra_two_procs rank %d", rank));
 
-    err = ompi_datatype_get_extent (sdtype, &lb, &sext);
-    if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    if (MPI_IN_PLACE != sbuf) {
+        err = ompi_datatype_get_extent (sdtype, &lb, &sext);
+        if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
+    }
 
     err = ompi_datatype_get_extent (rdtype, &lb, &rext);
     if (MPI_SUCCESS != err) { line = __LINE__; goto err_hndl; }
Index: ompi/mca/coll/tuned/coll_tuned_scatter.c
===================================================================
--- ompi/mca/coll/tuned/coll_tuned_scatter.c	(revision 27511)
+++ ompi/mca/coll/tuned/coll_tuned_scatter.c	(working copy)
@@ -60,8 +60,15 @@
 
     ompi_datatype_get_extent(sdtype, &slb, &sextent);
     ompi_datatype_get_true_extent(sdtype, &strue_lb, &strue_extent);
-    ompi_datatype_get_extent(rdtype, &rlb, &rextent);
-    ompi_datatype_get_true_extent(rdtype, &rtrue_lb, &rtrue_extent);
+    if (rank == root) {
+        if (rbuf != MPI_IN_PLACE) {
+            ompi_datatype_get_extent(rdtype, &rlb, &rextent);
+            ompi_datatype_get_true_extent(rdtype, &rtrue_lb, &rtrue_extent);
+        }
+    } else {
+        ompi_datatype_get_extent(rdtype, &rlb, &rextent);
+        ompi_datatype_get_true_extent(rdtype, &rtrue_lb, &rtrue_extent);
+    }
 
     vrank = (rank - root + size) % size;
     ptmp = (char *) rbuf;  /* by default suppose leaf nodes, just use rbuf */
Index: ompi/mca/coll/tuned/coll_tuned_gather.c
===================================================================
--- ompi/mca/coll/tuned/coll_tuned_gather.c	(revision 27511)
+++ ompi/mca/coll/tuned/coll_tuned_gather.c	(working copy)
@@ -60,8 +60,15 @@
     COLL_TUNED_UPDATE_IN_ORDER_BMTREE( comm, tuned_module, root );
     bmtree = data->cached_in_order_bmtree;
 
-    ompi_datatype_get_extent(sdtype, &slb, &sextent);
-    ompi_datatype_get_true_extent(sdtype, &strue_lb, &strue_extent);
+    if (rank == root) {
+        if (MPI_IN_PLACE != sbuf) {
+            ompi_datatype_get_extent(sdtype, &slb, &sextent);
+            ompi_datatype_get_true_extent(sdtype, &strue_lb, &strue_extent);
+        }
+    } else {
+        ompi_datatype_get_extent(sdtype, &slb, &sextent);
+        ompi_datatype_get_true_extent(sdtype, &strue_lb, &strue_extent);
+    }
 
     vrank = (rank - root + size) % size;
 
Index: ompi/mca/coll/tuned/coll_tuned_decision_fixed.c
===================================================================
--- ompi/mca/coll/tuned/coll_tuned_decision_fixed.c	(revision 27511)
+++ ompi/mca/coll/tuned/coll_tuned_decision_fixed.c	(working copy)
@@ -534,8 +534,13 @@
     }
 
     /* Determine complete data size */
-    ompi_datatype_type_size(sdtype, &dsize);
-    total_dsize = dsize * (ptrdiff_t)scount * (ptrdiff_t)communicator_size;   
+    if (MPI_IN_PLACE != sbuf) {
+        ompi_datatype_type_size(sdtype, &dsize);
+        total_dsize = dsize * (ptrdiff_t)scount * (ptrdiff_t)communicator_size; 
+    } else {
+        ompi_datatype_type_size(rdtype, &dsize);
+        total_dsize = dsize * (ptrdiff_t)rcount * (ptrdiff_t)communicator_size; 
+    }
    
     OPAL_OUTPUT((ompi_coll_tuned_stream, "ompi_coll_tuned_allgather_intra_dec_fixed"
                  " rank %d com_size %d msg_length %lu",
@@ -629,7 +634,11 @@
     }
     
     /* Determine complete data size */
-    ompi_datatype_type_size(sdtype, &dsize);
+    if (MPI_IN_PLACE != sbuf) {
+        ompi_datatype_type_size(sdtype, &dsize);
+    } else {
+        ompi_datatype_type_size(rdtype, &dsize);
+    }
     total_dsize = 0;
     for (i = 0; i < communicator_size; i++) {
         total_dsize += dsize * (ptrdiff_t)rcounts[i];