diff --git a/.gitignore b/.gitignore
index 6c958f7..8deef0c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -32,3 +32,5 @@ collective-big-count/test_reduce
 collective-big-count/test_scatter
 collective-big-count/test_scatterv
 collective-big-count/*_uniform_count
+
+comm_split_type/cmsplit_type
diff --git a/comm_split_type/Makefile b/comm_split_type/Makefile
new file mode 100644
index 0000000..2419a43
--- /dev/null
+++ b/comm_split_type/Makefile
@@ -0,0 +1,14 @@
+
+CFLAGS = -g -O0
+MPICC = mpicc
+
+PROGS = cmsplit_type
+
+all: $(PROGS)
+
+cmsplit_type: cmsplit_type.c
+	$(MPICC) cmsplit_type.c $(CFLAGS) -o cmsplit_type
+
+clean:
+	rm $(PROGS)
+
diff --git a/comm_split_type/cmsplit_type.c b/comm_split_type/cmsplit_type.c
new file mode 100644
index 0000000..e1426aa
--- /dev/null
+++ b/comm_split_type/cmsplit_type.c
@@ -0,0 +1,278 @@
+/*
+ * Modified / Simplified version of MPICH MPI test suite version
+ * for Open MPI specific split_topo values:
+ *  mpich-testsuite-4.1a1/comm/cmsplit_type.c
+ *
+ */
+
+#include "mpi.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+static const char *split_topo[] = {
+                                   "mpi_shared_memory",
+                                   "hwthread",
+                                   "core",
+                                   "l1cache",
+                                   "l2cache",
+                                   "l3cache",
+                                   "socket",
+                                   "numanode",
+                                   "board",
+                                   "host",
+                                   "cu",
+                                   "cluster",
+                                   NULL
+};
+
+int verbose = 0;
+int mcw_rank = 0;
+int mcw_size = 0;
+
+static void sync_hr(void) {
+    if (verbose) {
+        fflush(NULL);
+        MPI_Barrier(MPI_COMM_WORLD);
+        if (mcw_rank == 0) {
+            printf("-----------------------------------\n");
+            usleep(1000000);
+        }
+        fflush(NULL);
+        MPI_Barrier(MPI_COMM_WORLD);
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    int rank, size, errs = 0, tot_errs = 0;
+    int i;
+    MPI_Comm comm;
+    MPI_Info info;
+    int ret;
+
+    MPI_Init(&argc, &argv);
+    MPI_Comm_rank(MPI_COMM_WORLD, &mcw_rank);
+    MPI_Comm_size(MPI_COMM_WORLD, &mcw_size);
+
+    /*
+     * Verbosity
+     */
+    if (getenv("MPITEST_VERBOSE")) {
+        verbose = 1;
+    }
+    MPI_Bcast(&verbose, 1, MPI_INT, 0, MPI_COMM_WORLD);
+
+    /*
+     * Check to see if MPI_COMM_TYPE_SHARED works correctly
+     */
+    MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_SHARED, 0, MPI_INFO_NULL, &comm);
+    if (comm == MPI_COMM_NULL) {
+        printf("MPI_COMM_TYPE_SHARED (no hint): got MPI_COMM_NULL\n");
+        errs++;
+    } else {
+        MPI_Comm_rank(comm, &rank);
+        MPI_Comm_size(comm, &size);
+        if (rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_SHARED (no hint): Created shared subcommunicator of size %d\n",
+                   size);
+        }
+        MPI_Comm_free(&comm);
+    }
+
+    sync_hr();
+
+    /*
+     * Test MPI_COMM_TYPE_HW_GUIDED:
+     *  - Test with "mpi_hw_resource_type" = "mpi_shared_memory"
+     */
+    MPI_Info_create(&info);
+    MPI_Info_set(info, "mpi_hw_resource_type", "mpi_shared_memory");
+    if (mcw_rank == 0 && verbose) {
+        printf("MPI_COMM_TYPE_HW_GUIDED: Trying MPI Standard value %s\n", "mpi_shared_memory");
+    }
+    ret = MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_GUIDED, 0, info, &comm);
+    if (ret != MPI_SUCCESS) {
+        printf("MPI_COMM_TYPE_HW_GUIDED (%s) failed\n", split_topo[i]);
+        errs++;
+    } else if (comm != MPI_COMM_NULL) {
+        MPI_Comm_rank(comm, &rank);
+        MPI_Comm_size(comm, &size);
+        if (rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_HW_GUIDED (%s): Created shared subcommunicator of size %d\n",
+                   "mpi_shared_memory", size);
+        }
+        MPI_Comm_free(&comm);
+    }
+    MPI_Info_free(&info);
+
+    sync_hr();
+
+    /*
+     * Test MPI_COMM_TYPE_HW_GUIDED:
+     *  - Test with a variety of supported info values
+     */
+    for (i = 0; split_topo[i]; i++) {
+        MPI_Info_create(&info);
+        MPI_Info_set(info, "mpi_hw_resource_type", split_topo[i]);
+        if (mcw_rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_HW_GUIDED: Trying value %s\n", split_topo[i]);
+        }
+        ret = MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_GUIDED, 0, info, &comm);
+        /* result will depend on platform and process bindings, just check returns */
+        if (ret != MPI_SUCCESS) {
+            printf("MPI_COMM_TYPE_HW_GUIDED (%s) failed\n", split_topo[i]);
+            errs++;
+        } else if (comm != MPI_COMM_NULL) {
+            MPI_Comm_rank(comm, &rank);
+            MPI_Comm_size(comm, &size);
+            if (rank == 0 && verbose) {
+                printf("MPI_COMM_TYPE_HW_GUIDED (%s): Created shared subcommunicator of size %d\n",
+                       split_topo[i], size);
+            }
+            MPI_Comm_free(&comm);
+        }
+        MPI_Info_free(&info);
+        sync_hr();
+    }
+
+    /*
+     * Test MPI_COMM_TYPE_HW_GUIDED:
+     *  - pass MPI_INFO_NULL, it must return MPI_COMM_NULL.
+     */
+    if (mcw_rank == 0 && verbose) {
+        printf("MPI_COMM_TYPE_HW_GUIDED: Trying MPI_INFO_NULL\n");
+    }
+    info = MPI_INFO_NULL;
+    MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_GUIDED, 0, info, &comm);
+    if (comm != MPI_COMM_NULL) {
+        printf("MPI_COMM_TYPE_HW_GUIDED with MPI_INFO_NULL didn't return MPI_COMM_NULL\n");
+        errs++;
+        MPI_Comm_free(&comm);
+    } else {
+        if (mcw_rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_HW_GUIDED: Trying MPI_INFO_NULL - Passed\n");
+        }
+    }
+
+    sync_hr();
+
+    /*
+     * Test MPI_COMM_TYPE_HW_GUIDED:
+     *  - info without correct key, it must return MPI_COMM_NULL.
+     */
+    if (mcw_rank == 0 && verbose) {
+        printf("MPI_COMM_TYPE_HW_GUIDED: Trying invalid key\n");
+    }
+    MPI_Info_create(&info);
+    MPI_Info_set(info, "bogus_key", split_topo[0]);
+    MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_GUIDED, 0, info, &comm);
+    if (comm != MPI_COMM_NULL) {
+        printf("MPI_COMM_TYPE_HW_GUIDED without correct key didn't return MPI_COMM_NULL\n");
+        errs++;
+        MPI_Comm_free(&comm);
+    } else {
+        if (mcw_rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_HW_GUIDED: Trying invalid key - Passed\n");
+        }
+    }
+    MPI_Info_free(&info);
+
+    sync_hr();
+
+    /*
+     * Test MPI_COMM_TYPE_HW_GUIDED:
+     *  - info with correct key, but different values a different ranks, it must throw an error
+     */
+#if 0
+    for (i = 0; NULL != split_topo[i]; i++) {
+        ;
+    }
+    if (i < 2) {
+        if (mcw_rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_HW_GUIDED: Trying mismatched values -- SKIPPED not enough valid values (%d)\n", i);
+        }
+    } else {
+        if (mcw_rank == 0 && verbose) {
+            printf("MPI_COMM_TYPE_HW_GUIDED: Trying mismatched values\n");
+        }
+        MPI_Info_create(&info);
+        if (mcw_rank == 0) {
+            MPI_Info_set(info, "mpi_hw_resource_type", split_topo[0]);
+        } else {
+            MPI_Info_set(info, "mpi_hw_resource_type", split_topo[1]);
+        }
+        MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_GUIDED, 0, info, &comm);
+        if (comm != MPI_COMM_NULL) {
+            printf("MPI_COMM_TYPE_HW_GUIDED with mismatched values key didn't return MPI_COMM_NULL\n");
+            errs++;
+            MPI_Comm_free(&comm);
+        }
+        MPI_Info_free(&info);
+    }
+#endif
+
+    /* Test MPI_COMM_TYPE_HW_GUIDED:
+     *  - info with semantically matching split_types and keys, it must throw an error
+     */
+#if 0
+    if (mcw_rank == 0 && verbose) {
+        printf("MPI_COMM_TYPE_HW_GUIDED: Trying mismatched keys but semantically matching\n");
+    }
+
+    if (mcw_rank == 0) {
+        MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_SHARED, 0, MPI_INFO_NULL, &comm);
+    } else {
+        MPI_Info_create(&info);
+        MPI_Info_set(info, "mpi_hw_resource_type", "mpi_shared_memory");
+        MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_GUIDED, 0, info, &comm);
+    }
+    if (comm != MPI_COMM_NULL) {
+        printf("MPI_COMM_TYPE_HW_GUIDED with mismatched values key didn't return MPI_COMM_NULL\n");
+        errs++;
+        MPI_Comm_free(&comm);
+    }
+    MPI_Info_free(&info);
+#endif
+
+    /* Test MPI_COMM_TYPE_HW_UNGUIDED:
+     *  - TODO
+     */
+#if 0
+    if (mcw_rank == 0 && verbose)
+        printf("MPI_COMM_TYPE_HW_UNGUIDED: Trying basic\n");
+    MPI_Info_create(&info);
+    MPI_Comm_split_type(MPI_COMM_WORLD, MPI_COMM_TYPE_HW_UNGUIDED, 0, info, &comm);
+    if (comm != MPI_COMM_NULL) {
+        int newsize;
+        MPI_Comm_size(comm, &newsize);
+        if (!(newsize < mcw_size)) {
+            printf("MPI_COMM_TYPE_HW_UNGUIDED: Expected comm to be a proper sub communicator\n");
+            errs++;
+        }
+        char resource_type[100] = "";
+        int has_key = 0;
+        MPI_Info_get(info, "mpi_hw_resource_type", 100, resource_type, &has_key);
+        if (!has_key || strlen(resource_type) == 0) {
+            printf("MPI_COMM_TYPE_HW_UNGUIDED: info for mpi_hw_resource_type not returned\n");
+            errs++;
+        }
+
+        MPI_Comm_free(&comm);
+    }
+    else if (mcw_rank == 0 && verbose) {
+        printf("MPI_COMM_TYPE_HW_UNGUIDED: Returned MPI_COMM_NULL\n");
+    }
+#endif
+
+    /*
+     * All done - figure out if we passed
+     */
+ done:
+    MPI_Reduce(&errs, &tot_errs, 1, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
+
+    MPI_Finalize();
+
+    return tot_errs;
+}