1 files changed, 17 insertions, 0 deletions
diff --git a/src/H5Fistore.c b/src/H5Fistore.c
index 3a54612..dcd1d35 100644
--- a/src/H5Fistore.c
+++ b/src/H5Fistore.c
@@ -1998,6 +1998,9 @@ H5F_istore_get_addr (H5F_t *f, const H5O_layout_t *layout,
  *
  * Modifications:
  *
+ * rky 980923
+ * Added barrier to preclude racing with data writes.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
@@ -2092,6 +2095,20 @@ H5F_istore_allocate (H5F_t *f, const H5O_layout_t *layout,
 	if (carry) break;
     }
 
+    /*
+     * rky 980923
+     * The following barrier is a temporary fix to prevent overwriting
+     * real data caused by a race between one proc's call of H5F_istore_allocate
+     * (from H5D_allocate, ultimately from H5Dcreate and H5Dextend)
+     * and another proc's call of H5Dwrite.
+     * Eventually, this barrier should be removed,
+     * when H5D_allocate is changed to call H5MF_alloc directly
+     * to allocate space, instead of calling H5F_istore_unlock.
+     */
+    if (MPI_Barrier( f->shared->access_parms->u.mpio.comm )) {
+	HRETURN_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "MPI_Barrier failed");
+    }
+
     FUNC_LEAVE(SUCCEED);
 }
 #endif