[svn-r18650] Description:

	Bring back various minor tweaks & cleanups from the revise_chunks
branch.

Tested on:
        FreeBSD/32 6.3 (duty) in debug mode
        FreeBSD/64 6.3 (liberty) w/C++ & FORTRAN, in debug mode
        Linux/32 2.6 (jam) w/PGI compilers, w/default API=1.8.x,
                w/C++ & FORTRAN, w/threadsafe, in debug mode
        Linux/64-amd64 2.6 (amani) w/Intel compilers, w/default API=1.6.x,
                w/C++ & FORTRAN, in production mode
        Solaris/32 2.10 (linew) w/deprecated symbols disabled, w/C++ & FORTRAN,
                w/szip filter, in production mode
        Linux/64-ia64 2.6 (cobalt) w/Intel compilers, w/C++ & FORTRAN,
                in production mode
        Linux/64-ia64 2.4 (tg-login3) w/parallel, w/FORTRAN, in debug mode
        Linux/64-amd64 2.6 (abe) w/parallel, w/FORTRAN, in production mode

29 files changed, 95 insertions, 53 deletions

diff --git a/src/H5C.c b/src/H5C.c
index 5c8a8cd..2289a42 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -5957,8 +5957,8 @@ H5C_adjust_flush_dependency_rc(H5C_cache_entry_t * cache_entry,
  * Function:    H5C_create_flush_dependency()
  *
  * Purpose:	Initiates a parent<->child entry flush dependency.  The parent
- *              entry must be protected at the time of call, and must have all
- *              dependencies removed before the cache can shut down.
+ *              entry must be pinned or protected at the time of call, and must
+ *              have all dependencies removed before the cache can shut down.
  *
  * Note:	Flush dependencies in the cache indicate that a child entry
  *              must be flushed to the file before its parent.  (This is
@@ -5971,8 +5971,7 @@ H5C_adjust_flush_dependency_rc(H5C_cache_entry_t * cache_entry,
  *              dependency height of its children.
  *
  *              Creating a flush dependency between two entries will also pin
- *              the parent entry.  (The parent entry must _not_ be pinned
- *              through some other mechanism)
+ *              the parent entry.
  *
  * Return:      Non-negative on success/Negative on failure
  *
diff --git a/src/H5D.c b/src/H5D.c
index da8b0a6..30ce594 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -27,7 +27,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Dpkg.h"		/* Datasets 				*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5FLprivate.h"	/* Free lists                           */
diff --git a/src/H5Dbtree.c b/src/H5Dbtree.c
index a7e61ce..374c1b6 100644
--- a/src/H5Dbtree.c
+++ b/src/H5Dbtree.c
@@ -33,7 +33,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Bprivate.h"		/* B-link trees				*/
 #include "H5Dpkg.h"		/* Datasets				*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
diff --git a/src/H5Dchunk.c b/src/H5Dchunk.c
index 2e0b096..9b9298e 100644
--- a/src/H5Dchunk.c
+++ b/src/H5Dchunk.c
@@ -51,7 +51,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Dpkg.h"		/* Dataset functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5FLprivate.h"	/* Free Lists                           */
@@ -511,7 +510,7 @@ H5D_chunk_init(H5F_t *f, hid_t dxpl_id, const H5D_t *dset, hid_t dapl_id)
     if(dset->shared->layout.storage.u.chunk.ops->init && (dset->shared->layout.storage.u.chunk.ops->init)(&idx_info, dset->shared->space, dset->oloc.addr) < 0)
 	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't initialize indexing information")
 
-    /* Set the number of chunks in dataset */
+    /* Set the number of chunks in dataset, etc. */
     if(H5D_chunk_set_info(dset) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to set # of chunks for dataset")
 
diff --git a/src/H5Dcontig.c b/src/H5Dcontig.c
index ca3b09e..567f4c9 100644
--- a/src/H5Dcontig.c
+++ b/src/H5Dcontig.c
@@ -34,7 +34,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Dpkg.h"		/* Dataset functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Fprivate.h"		/* Files				*/
diff --git a/src/H5Ddbg.c b/src/H5Ddbg.c
index 2feb773..fa4c54c 100644
--- a/src/H5Ddbg.c
+++ b/src/H5Ddbg.c
@@ -27,7 +27,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Dpkg.h"		/* Datasets 				*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Iprivate.h"		/* IDs			  		*/
diff --git a/src/H5Ddeprec.c b/src/H5Ddeprec.c
index cecf4a2..b06bce1 100644
--- a/src/H5Ddeprec.c
+++ b/src/H5Ddeprec.c
@@ -41,7 +41,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Dpkg.h"		/* Datasets 				*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Iprivate.h"		/* IDs			  		*/
diff --git a/src/H5Dfill.c b/src/H5Dfill.c
index 7180c8c..f418a81 100644
--- a/src/H5Dfill.c
+++ b/src/H5Dfill.c
@@ -34,7 +34,6 @@
 /* Headers */
 /***********/
 #include "H5private.h"		/* Generic Functions			*/
-#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Dpkg.h"		/* Dataset functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5FLprivate.h"	/* Free Lists                           */
diff --git a/src/H5Dint.c b/src/H5Dint.c
index cef551a..6253aa6 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -797,9 +797,11 @@ H5D_update_oh_info(H5F_t *file, hid_t dxpl_id, H5D_t *dset, hid_t dapl_id)
     if(NULL == (oh = H5O_pin(oloc, dxpl_id)))
         HGOTO_ERROR(H5E_DATASET, H5E_CANTPIN, FAIL, "unable to pin dataset object header")
 
-    /* Update the datatype and dataspace header messages */
+    /* Write the dataspace header message */
     if(H5S_append(file, dxpl_id, oh, dset->shared->space) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update dataspace header message")
+
+    /* Write the datatype header message */
     if(H5O_msg_append_oh(file, dxpl_id, oh, H5O_DTYPE_ID, H5O_MSG_FLAG_CONSTANT, 0, type) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update datatype header message")
 
diff --git a/src/H5Dlayout.c b/src/H5Dlayout.c
index 0245bec..6aa5b44 100644
--- a/src/H5Dlayout.c
+++ b/src/H5Dlayout.c
@@ -441,7 +441,7 @@ done:
 /*-------------------------------------------------------------------------
  * Function:	H5D_layout_oh_write
  *
- * Purpose:	Read layout/pline/efl information for dataset
+ * Purpose:	Write layout/pline/efl information for dataset
  *
  * Return:	Success:    SUCCEED
  *		Failure:    FAIL
diff --git a/src/H5Dpkg.h b/src/H5Dpkg.h
index 38f1ab4..dbd495c 100644
--- a/src/H5Dpkg.h
+++ b/src/H5Dpkg.h
@@ -32,6 +32,7 @@
 #include "H5Dprivate.h"
 
 /* Other private headers needed by this file */
+#include "H5ACprivate.h"	/* Metadata cache			*/
 #include "H5Gprivate.h"		/* Groups 			  	*/
 #include "H5SLprivate.h"	/* Skip lists				*/
 #include "H5Tprivate.h"		/* Datatypes         			*/
diff --git a/src/H5EA.c b/src/H5EA.c
index f8a2969..cca51a8 100644
--- a/src/H5EA.c
+++ b/src/H5EA.c
@@ -87,7 +87,7 @@ typedef herr_t (*H5EA__unprotect_func_t)(void *thing, hid_t dxpl_id,
 extern const H5EA_class_t H5EA_CLS_TEST[1];
 
 const H5EA_class_t *const H5EA_client_class_g[] = {
-    H5EA_CLS_TEST,		/* 0 - H5EA_TEST_ID 			*/
+    H5EA_CLS_TEST,		/* ? - H5EA_CLS_TEST_ID			*/
 };
 
 
@@ -820,7 +820,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     /* Set the shared array header's file context for this operation */
     hdr->f = ea->f;
 
-    /* Set up flush dependency between child_entry and metadata array 'thing' */
+    /* Set up flush dependency between parent entry and extensible array header */
     if(H5EA__create_flush_depend(parent_entry, (H5AC_info_t *)hdr) < 0)
         H5E_THROW(H5E_CANTDEPEND, "unable to create flush dependency on file metadata")
 
@@ -863,7 +863,7 @@ HDfprintf(stderr, "%s: Called\n", FUNC);
     /* Set the shared array header's file context for this operation */
     hdr->f = ea->f;
 
-    /* Remove flush dependency between child_entry and metadata array 'thing' */
+    /* Remove flush dependency between parent entry and extensible array header */
     if(H5EA__destroy_flush_depend(parent_entry, (H5AC_info_t *)hdr) < 0)
         H5E_THROW(H5E_CANTUNDEPEND, "unable to destroy flush dependency on file metadata")
 
diff --git a/src/H5EAtest.c b/src/H5EAtest.c
index 58da489..87f9195 100644
--- a/src/H5EAtest.c
+++ b/src/H5EAtest.c
@@ -50,6 +50,7 @@
 /* Sanity checking value for callback contexts */
 #define H5EA__TEST_BOGUS_VAL    42
 
+
 /******************/
 /* Local Typedefs */
 /******************/
@@ -60,6 +61,7 @@ typedef struct H5EA__test_ctx_t {
     H5EA__ctx_cb_t *cb;         /* Pointer to context's callback action */
 } H5EA__test_ctx_t;
 
+
 /********************/
 /* Package Typedefs */
 /********************/
diff --git a/src/H5FA.c b/src/H5FA.c
index b235ef9..a30a4aa 100644
--- a/src/H5FA.c
+++ b/src/H5FA.c
@@ -78,7 +78,7 @@
 extern const H5FA_class_t H5FA_CLS_TEST[1];
 
 const H5FA_class_t *const H5FA_client_class_g[] = {
-    H5FA_CLS_TEST,		/* 0 - H5FA_TEST_ID 			*/
+    H5FA_CLS_TEST,		/* ? - H5FA_CLS_TEST_ID 		*/
 };
 
 
diff --git a/src/H5FApkg.h b/src/H5FApkg.h
index ddc4c59..9f82a32 100644
--- a/src/H5FApkg.h
+++ b/src/H5FApkg.h
@@ -224,9 +224,7 @@ H5_DLLVAR const H5FA_class_t H5FA_CLS_CHUNK[1];
 H5_DLLVAR const H5FA_class_t H5FA_CLS_FILT_CHUNK[1];
 
 /* Internal fixed array testing class */
-#ifdef H5FA_TESTING
 H5_DLLVAR const H5FA_class_t H5FA_CLS_TEST[1];
-#endif /* H5FA_TESTING */
 
 /* Array of fixed array client ID -> client class mappings */
 extern const H5FA_class_t *const H5FA_client_class_g[H5FA_NUM_CLS_ID];
diff --git a/src/H5FDcore.c b/src/H5FDcore.c
index 3a56524..b3cc84d 100644
--- a/src/H5FDcore.c
+++ b/src/H5FDcore.c
@@ -900,7 +900,7 @@ H5FD_core_read(H5FD_t *_file, H5FD_mem_t UNUSED type, hid_t UNUSED dxpl_id, hadd
         HGOTO_ERROR(H5E_IO, H5E_OVERFLOW, FAIL, "file address overflowed")
     if (REGION_OVERFLOW(addr, size))
         HGOTO_ERROR(H5E_IO, H5E_OVERFLOW, FAIL, "file address overflowed")
-    if (addr + size > file->eoa)
+    if((addr + size) > file->eoa)
         HGOTO_ERROR(H5E_IO, H5E_OVERFLOW, FAIL, "file address overflowed")
 
     /* Read the part which is before the EOF marker */
diff --git a/src/H5FDdirect.c b/src/H5FDdirect.c
index fff31f3..8219941 100644
--- a/src/H5FDdirect.c
+++ b/src/H5FDdirect.c
@@ -928,7 +928,7 @@ H5FD_direct_read(H5FD_t *_file, H5FD_mem_t UNUSED type, hid_t UNUSED dxpl_id, ha
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "addr undefined")
     if (REGION_OVERFLOW(addr, size))
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
-    if (addr+size>file->eoa)
+    if((addr + size) > file->eoa)
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
 
     /* If the system doesn't require data to be aligned, read the data in
diff --git a/src/H5FDlog.c b/src/H5FDlog.c
index 0da5765..c21fc92 100644
--- a/src/H5FDlog.c
+++ b/src/H5FDlog.c
@@ -1056,7 +1056,7 @@ H5FD_log_read(H5FD_t *_file, H5FD_mem_t type, hid_t UNUSED dxpl_id, haddr_t addr
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "addr undefined")
     if (REGION_OVERFLOW(addr, size))
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
-    if (addr+size>file->eoa)
+    if((addr + size) > file->eoa)
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
 
     /* Log the I/O information about the read */
diff --git a/src/H5FDmpiposix.c b/src/H5FDmpiposix.c
index ff5b118..d5e58e9 100644
--- a/src/H5FDmpiposix.c
+++ b/src/H5FDmpiposix.c
@@ -1131,7 +1131,7 @@ H5FD_mpiposix_read(H5FD_t *_file, H5FD_mem_t UNUSED type, hid_t UNUSED dxpl_id,
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "addr undefined")
     if (REGION_OVERFLOW(addr, size))
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
-    if (addr+size>file->eoa)
+    if((addr + size) > file->eoa)
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
 
 #ifdef REPORT_IO
diff --git a/src/H5FDstdio.c b/src/H5FDstdio.c
index 7fffbd4..b241f4d 100644
--- a/src/H5FDstdio.c
+++ b/src/H5FDstdio.c
@@ -791,8 +791,8 @@ H5FD_stdio_read(H5FD_t *_file, H5FD_mem_t type, hid_t dxpl_id, haddr_t addr, siz
         H5Epush_ret (func, H5E_ERR_CLS, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1)
     if (REGION_OVERFLOW(addr, size))
         H5Epush_ret (func, H5E_ERR_CLS, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1)
-    if (addr+size>file->eoa)
-        H5Epush_ret (func, H5E_ERR_CLS, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1)
+    if((addr + size) > file->eoa)
+        H5Epush_ret(func, H5E_ERR_CLS, H5E_IO, H5E_OVERFLOW, "file address overflowed", -1)
 
     /* Check easy cases */
     if (0 == size)
diff --git a/src/H5FDwindows.c b/src/H5FDwindows.c
index aca03c8..47c7f2d 100644
--- a/src/H5FDwindows.c
+++ b/src/H5FDwindows.c
@@ -799,7 +799,7 @@ H5FD_windows_read(H5FD_t *_file, H5FD_mem_t UNUSED type, hid_t UNUSED dxpl_id, h
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "addr undefined")
     if (REGION_OVERFLOW(addr, size))
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
-    if (addr+size>file->eoa)
+    if((addr + size) > file->eoa)
         HGOTO_ERROR(H5E_ARGS, H5E_OVERFLOW, FAIL, "addr overflow")
 
     /* Seek to the correct location */
diff --git a/src/H5Fsuper_cache.c b/src/H5Fsuper_cache.c
index f5e5a75..cb74322 100644
--- a/src/H5Fsuper_cache.c
+++ b/src/H5Fsuper_cache.c
@@ -183,7 +183,7 @@ H5F_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t UNUSED addr, const void UNUSED
     HDassert(fixed_size + variable_size <= sizeof(sbuf));
 
     /* Read in variable-sized portion of superblock */
-    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, (haddr_t)fixed_size + variable_size) < 0)
+    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, (haddr_t)(fixed_size + variable_size)) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
     if(H5FD_read(lf, dxpl_id, H5FD_MEM_SUPER, (haddr_t)fixed_size, variable_size, p) < 0)
         HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read superblock")
diff --git a/src/H5O.c b/src/H5O.c
index a2b592b..340f88e 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -125,8 +125,8 @@ const H5O_msg_class_t *const H5O_msg_class_g[] = {
     H5O_MSG_DRVINFO,		/*0x0014 Driver info settings		*/
     H5O_MSG_AINFO,		/*0x0015 Attribute information		*/
     H5O_MSG_REFCOUNT,		/*0x0016 Object's ref. count		*/
-    H5O_MSG_FSINFO,		/*0x0018 Free-space manager info message */
-    H5O_MSG_UNKNOWN,		/*0x0017 Placeholder for unknown message */
+    H5O_MSG_FSINFO,		/*0x0017 Free-space manager info message */
+    H5O_MSG_UNKNOWN,		/*0x0018 Placeholder for unknown message */
 };
 
 /* Declare a free list to manage the H5O_t struct */
diff --git a/src/H5Oalloc.c b/src/H5Oalloc.c
index 6b921f2..64d2f03 100644
--- a/src/H5Oalloc.c
+++ b/src/H5Oalloc.c
@@ -1128,7 +1128,10 @@ H5O_alloc(H5F_t *f, hid_t dxpl_id, H5O_t *oh, const H5O_msg_class_t *type,
     HDassert(mesg);
 
     /* Compute the size needed to store the message in the object header */
-    if((raw_size = (type->raw_size)(f, FALSE, mesg)) >= H5O_MESG_MAX_SIZE)
+    raw_size = (type->raw_size)(f, FALSE, mesg);
+    if(0 == raw_size)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "can't compute object header message size")
+    if(raw_size >= H5O_MESG_MAX_SIZE)
         HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "object header message is too large")
     aligned_size = H5O_ALIGN_OH(oh, raw_size);
 
diff --git a/src/H5Olayout.c b/src/H5Olayout.c
index a34dcc2..67dbf4d 100644
--- a/src/H5Olayout.c
+++ b/src/H5Olayout.c
@@ -58,15 +58,15 @@ const H5O_msg_class_t H5O_MSG_LAYOUT[1] = {{
     H5O_layout_encode,      	/*encode message                */
     H5O_layout_copy,        	/*copy the native value         */
     H5O_layout_size,        	/*size of message on disk       */
-    H5O_layout_reset,           /*reset method                  */
+    H5O_layout_reset,		/*reset method                  */
     H5O_layout_free,        	/*free the struct		*/
     H5O_layout_delete,	        /* file delete method		*/
     NULL,			/* link method			*/
     NULL,			/*set share method		*/
     NULL,		    	/*can share method		*/
     NULL,			/* pre copy native value to file */
-    H5O_layout_copy_file,       /* copy native value to file    */
-    NULL,		        /* post copy native value to file    */
+    H5O_layout_copy_file,	/* copy native value to file    */
+    NULL,		        /* post copy native value to file */
     NULL,			/* get creation index		*/
     NULL,			/* set creation index		*/
     H5O_layout_debug       	/*debug the message             */
@@ -589,6 +589,7 @@ H5O_layout_copy_file(H5F_t *file_src, void *mesg_src, H5F_t *file_dst,
     FUNC_ENTER_NOAPI_NOINIT(H5O_layout_copy_file)
 
     /* check args */
+    HDassert(file_src);
     HDassert(layout_src);
     HDassert(file_dst);
 
diff --git a/src/H5Opkg.h b/src/H5Opkg.h
index 7e1ff4c..b64cf64 100644
--- a/src/H5Opkg.h
+++ b/src/H5Opkg.h
@@ -504,6 +504,7 @@ H5_DLLVAR const H5O_msg_class_t H5O_MSG_FSINFO[1];
 /* Placeholder for unknown message. (0x0018) */
 H5_DLLVAR const H5O_msg_class_t H5O_MSG_UNKNOWN[1];
 
+
 /*
  * Object header "object" types
  */
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index eab5d2c..c38ddea 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -154,7 +154,7 @@ typedef struct H5O_copy_t {
 #define H5O_FILL_NEW_ID 0x0005          /* Fill Value Message. (New)  */
 #define H5O_LINK_ID     0x0006          /* Link Message. */
 #define H5O_EFL_ID	0x0007          /* External File List Message  */
-#define H5O_LAYOUT_ID	0x0008          /* Data Storage Layout Message.  */
+#define H5O_LAYOUT_ID	0x0008          /* Data Layout Message.  */
 #define H5O_BOGUS_ID	0x0009          /* "Bogus" Message.  */
 #define H5O_GINFO_ID	0x000a          /* Group info Message.  */
 #define H5O_PLINE_ID	0x000b          /* Filter pipeline message.  */
@@ -346,7 +346,12 @@ typedef struct H5O_efl_t {
  */
 #define H5O_LAYOUT_VERSION_3	3
 
-/* This version adds different types of indices to chunked datasets */
+/* This version adds different types of indices to chunked datasets, allows
+ *      for larger chunk dimensions, stores chunk indices into their own
+ *      message (the "layout index" message), adds features for compact/dense
+ *      storage of elements and/or chunk records, adds features for abbreviating
+ *      the storage used for partial chunks on boundaries, etc.
+ */
 #define H5O_LAYOUT_VERSION_4	4
 
 /* The latest version of the format.  Look through the 'encode'
diff --git a/src/H5V.c b/src/H5V.c
index 34cf714..48fa9ab 100644
--- a/src/H5V.c
+++ b/src/H5V.c
@@ -1132,6 +1132,47 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5V_array_calc_pre
+ *
+ * Purpose:	Given a linear offset in an array, the dimensions of that
+ *              array and the pre-computed 'down' (accumulator) sizes, this
+ *              function computes the coordinates of that offset in the array.
+ *
+ *		The dimensionality of the whole array, and the coordinates is N.
+ *              The array dimensions are TOTAL_SIZE and the coordinates
+ *              are returned in COORD.  The linear offset is in OFFSET.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		Thursday, July 16, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5V_array_calc_pre(hsize_t offset, unsigned n, const hsize_t *total_size,
+    const hsize_t *down, hsize_t *coords)
+{
+    unsigned    u;                      /* Local index variable */
+
+    FUNC_ENTER_NOAPI_NOFUNC(H5V_array_calc_pre)
+
+    /* Sanity check */
+    HDassert(n <= H5V_HYPER_NDIMS);
+    HDassert(total_size);
+    HDassert(coords);
+
+    /* Compute the coordinates from the offset */
+    for(u = 0; u < n; u++) {
+        coords[u] = offset / down[u];
+        offset %= down[u];
+    } /* end for */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5V_array_calc_pre() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5V_array_calc
  *
  * Purpose:	Given a linear offset in an array and the dimensions of that
@@ -1155,31 +1196,25 @@ herr_t
 H5V_array_calc(hsize_t offset, unsigned n, const hsize_t *total_size, hsize_t *coords)
 {
     hsize_t	idx[H5V_HYPER_NDIMS];	/* Size of each dimension in bytes */
-    hsize_t     acc;                    /* Size accumulator */
-    unsigned    u;                      /* Local index variable */
-    int         i;                      /* Local index variable */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI_NOFUNC(H5V_array_calc)
+    FUNC_ENTER_NOAPI(H5V_array_calc, FAIL)
 
     /* Sanity check */
-    assert(n <= H5V_HYPER_NDIMS);
-    assert(total_size);
-    assert(coords);
+    HDassert(n <= H5V_HYPER_NDIMS);
+    HDassert(total_size);
+    HDassert(coords);
 
     /* Build the sizes of each dimension in the array */
-    /* (From fastest to slowest) */
-    for(i=(int)(n-1),acc=1; i>=0; i--) {
-        idx[i]=acc;
-        acc *= total_size[i];
-    } /* end for */
+    if(H5V_array_down(n, total_size, idx) < 0)
+        HGOTO_ERROR(H5E_INTERNAL, H5E_BADVALUE, FAIL, "can't compute down sizes")
 
     /* Compute the coordinates from the offset */
-    for(u=0; u<n; u++) {
-        coords[u]=offset/idx[u];
-        offset %= idx[u];
-    } /* end for */
+    if(H5V_array_calc_pre(offset, n, total_size, idx, coords) < 0)
+        HGOTO_ERROR(H5E_INTERNAL, H5E_BADVALUE, FAIL, "can't compute coordinates")
 
-    FUNC_LEAVE_NOAPI(SUCCEED)
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5V_array_calc() */
 
 
diff --git a/src/H5Vprivate.h b/src/H5Vprivate.h
index 1dec0c0..e351f86 100644
--- a/src/H5Vprivate.h
+++ b/src/H5Vprivate.h
@@ -83,6 +83,8 @@ H5_DLL hsize_t H5V_array_offset_pre(unsigned n,
     const hsize_t *acc, const hsize_t *offset);
 H5_DLL hsize_t H5V_array_offset(unsigned n, const hsize_t *total_size,
     const hsize_t *offset);
+H5_DLL herr_t H5V_array_calc_pre(hsize_t offset, unsigned n, const hsize_t *total_size,
+    const hsize_t *down, hsize_t *coords);
 H5_DLL herr_t H5V_array_calc(hsize_t offset, unsigned n,
     const hsize_t *total_size, hsize_t *coords);
 H5_DLL herr_t H5V_chunk_index(unsigned ndims, const hsize_t *coord,