diff --git a/ompi/class/ompi_circular_buffer_fifo.h b/ompi/class/ompi_circular_buffer_fifo.h
index bf1b9f1984..c3ece39058 100644
--- a/ompi/class/ompi_circular_buffer_fifo.h
+++ b/ompi/class/ompi_circular_buffer_fifo.h
@@ -112,7 +112,7 @@ typedef struct ompi_cb_fifo_t ompi_cb_fifo_t;
  *
  */
 static inline void *ompi_cb_fifo_read_from_tail(ompi_cb_fifo_t *fifo,
-        bool flush_entries_read, bool *queue_empty, ssize_t offset) 
+        bool flush_entries_read, bool *queue_empty, ptrdiff_t offset) 
 {
     int index = 0,clearIndex, i;
     void **q_ptr;
diff --git a/ompi/class/ompi_fifo.h b/ompi/class/ompi_fifo.h
index 1dfc5c0d7c..648962c37b 100644
--- a/ompi/class/ompi_fifo.h
+++ b/ompi/class/ompi_fifo.h
@@ -429,7 +429,7 @@ void *ompi_fifo_read_from_tail_same_base_addr( ompi_fifo_t *fifo)
  *
  */
 static inline void *ompi_fifo_read_from_tail(ompi_fifo_t *fifo, 
-                                             ssize_t offset) 
+                                             ptrdiff_t offset) 
 {
     /* local parameters */
     void *return_value;
diff --git a/ompi/mca/btl/sm/btl_sm.c b/ompi/mca/btl/sm/btl_sm.c
index f5269a9a9f..444a824bf6 100644
--- a/ompi/mca/btl/sm/btl_sm.c
+++ b/ompi/mca/btl/sm/btl_sm.c
@@ -152,9 +152,9 @@ int mca_btl_sm_add_procs_same_base_addr(
     struct mca_btl_base_endpoint_t **peers,
     ompi_bitmap_t* reachability)
 {
-    int return_code=OMPI_SUCCESS, cnt,len;
-    size_t i,j,proc,size,n_to_allocate,length;
-    int32_t n_local_procs;
+    int return_code = OMPI_SUCCESS, cnt, len;
+    size_t i, j, size, n_to_allocate, length;
+    int32_t n_local_procs, proc;
     ompi_proc_t* my_proc; /* pointer to caller's proc structure */
     mca_btl_sm_t *btl_sm;
     ompi_fifo_t *my_fifos;
@@ -165,8 +165,8 @@ int mca_btl_sm_add_procs_same_base_addr(
     volatile int *tmp_int_ptr;
 
     /* initializion */
-    for(i=0 ; i < nprocs ; i++ ) {
-        peers[i]=NULL;
+    for( i = 0 ; i < nprocs ; i++ ) {
+        peers[i] = NULL;
     }
     btl_sm=(mca_btl_sm_t *)btl;
 
@@ -179,8 +179,8 @@ int mca_btl_sm_add_procs_same_base_addr(
     }
 
     /* initialize and sm_proc_connect*/
-    for(proc=0 ; proc < nprocs ; proc++ ) {
-        mca_btl_sm_component.sm_proc_connect[proc]=0;
+    for( proc = 0 ; proc < (int32_t)nprocs ; proc++ ) {
+        mca_btl_sm_component.sm_proc_connect[proc] = 0;
     }
 
     /* get pointer to my proc structure */
@@ -195,7 +195,7 @@ int mca_btl_sm_add_procs_same_base_addr(
      * host to shared memory reachbility list.  Also, get number
      * of local procs in the prcs list. */
     n_local_procs=0;
-    for( proc=0 ; proc < nprocs; proc++ ) {
+    for( proc=0 ; proc < (int32_t)nprocs; proc++ ) {
 #if OMPI_ENABLE_PROGRESS_THREADS == 1
         char path[PATH_MAX];
 #endif
@@ -285,8 +285,8 @@ int mca_btl_sm_add_procs_same_base_addr(
 
     if ( !mca_btl_sm[0].btl_inited ) {
         /* set the shared memory offset */
-        mca_btl_sm_component.sm_offset=(ssize_t *)
-            malloc(n_to_allocate*sizeof(ssize_t));
+        mca_btl_sm_component.sm_offset=(ptrdiff_t*)
+            malloc(n_to_allocate*sizeof(ptrdiff_t));
             if(NULL == mca_btl_sm_component.sm_offset ) {
             return_code=OMPI_ERR_OUT_OF_RESOURCE;
             goto CLEANUP;
@@ -303,7 +303,7 @@ int mca_btl_sm_add_procs_same_base_addr(
 
     /* set local proc's smp rank in the peers structure for
      * rapid access */
-    for( proc=0 ; proc < nprocs; proc++ ) {
+    for( proc=0 ; proc < (int32_t)nprocs; proc++ ) {
         struct mca_btl_base_endpoint_t* peer = peers[proc];
         if(NULL != peer) {
             mca_btl_sm_component.sm_peers[peer->peer_smp_rank] = peer;
@@ -575,7 +575,7 @@ int mca_btl_sm_add_procs_same_base_addr(
 
     /* set connectivity */
     cnt=0;
-    for(proc = 0 ; proc < nprocs ; proc++ ) {
+    for(proc = 0 ; proc < (int32_t)nprocs ; proc++ ) {
 
         struct mca_btl_base_endpoint_t* peer = peers[proc];
         if(peer == NULL)
diff --git a/ompi/mca/btl/sm/btl_sm.h b/ompi/mca/btl/sm/btl_sm.h
index 2bbc07945a..3eaa5e6f78 100644
--- a/ompi/mca/btl/sm/btl_sm.h
+++ b/ompi/mca/btl/sm/btl_sm.h
@@ -106,7 +106,7 @@ struct mca_btl_sm_component_t {
                              a real virtual address */
     size_t size_of_cb_queue; /**< size of each circular buffer queue array */
     size_t cb_lazy_free_freq; /**< frequency of lazy free */
-    ssize_t *sm_offset;        /**< offset to be applied to shared memory
+    ptrdiff_t *sm_offset;    /**< offset to be applied to shared memory
                               addresses, per local process value */
     int *sm_proc_connect;    /* scratch array used by the 0'th btl to
                               * set indicate sm connectivty.  Used by
diff --git a/ompi/mca/btl/sm/btl_sm_component.c b/ompi/mca/btl/sm/btl_sm_component.c
index 2d7f65888d..3232e72d79 100644
--- a/ompi/mca/btl/sm/btl_sm_component.c
+++ b/ompi/mca/btl/sm/btl_sm_component.c
@@ -474,9 +474,9 @@ int mca_btl_sm_component_progress(void)
             {
                 /* completion callback */
                 frag->base.des_src = 
-                    ( mca_btl_base_segment_t* )((unsigned char*)frag->base.des_dst + mca_btl_sm_component.sm_offset[peer_smp_rank]);
-                frag->base.des_src->seg_addr.pval =
-                    ((unsigned char*)frag->base.des_src->seg_addr.pval +
+                    ( mca_btl_base_segment_t* )((ptrdiff_t)frag->base.des_dst + mca_btl_sm_component.sm_offset[peer_smp_rank]);
+                frag->base.des_src->seg_addr.pval = (void*)
+                    ((ptrdiff_t)frag->base.des_src->seg_addr.pval +
                      mca_btl_sm_component.sm_offset[peer_smp_rank]);
                 frag->base.des_dst = frag->base.des_src;
                 frag->base.des_cbfunc(&mca_btl_sm[1].super, frag->endpoint, &frag->base, frag->rc);
@@ -487,9 +487,9 @@ int mca_btl_sm_component_progress(void)
                 /* recv upcall */
                 mca_btl_sm_recv_reg_t* reg = mca_btl_sm[1].sm_reg + frag->tag;
                 frag->base.des_dst = (mca_btl_base_segment_t*)
-                    ((unsigned char*)frag->base.des_src + mca_btl_sm_component.sm_offset[peer_smp_rank]);
-                frag->base.des_dst->seg_addr.pval = 
-                    ((unsigned char*)frag->base.des_dst->seg_addr.pval +
+                    ((ptrdiff_t)frag->base.des_src + mca_btl_sm_component.sm_offset[peer_smp_rank]);
+                frag->base.des_dst->seg_addr.pval = (void*)
+                    ((ptrdiff_t)frag->base.des_dst->seg_addr.pval +
                     mca_btl_sm_component.sm_offset[peer_smp_rank]);
                 frag->base.des_src = frag->base.des_dst;
                 reg->cbfunc(&mca_btl_sm[1].super,frag->tag,&frag->base,reg->cbdata);
diff --git a/ompi/mca/btl/sm/btl_sm_fifo.h b/ompi/mca/btl/sm/btl_sm_fifo.h
index d88fbd49a6..574c3b862f 100644
--- a/ompi/mca/btl/sm/btl_sm_fifo.h
+++ b/ompi/mca/btl/sm/btl_sm_fifo.h
@@ -15,8 +15,8 @@ do { \
     if(OMPI_CB_FREE == fifo->head) { \
         /* no queues have been allocated - allocate now */ \
         rc=ompi_fifo_init_same_base_addr( \
-            mca_btl_sm_component.size_of_cb_queue, \
-            mca_btl_sm_component.cb_lazy_free_freq, \
+            (int)mca_btl_sm_component.size_of_cb_queue, \
+            (int)mca_btl_sm_component.cb_lazy_free_freq, \
             /* at this stage we are not doing anything with memory \
             * locality */ \
             0,0,0, \