[svn-r30189] Description:

    Clean up more warnings: drop the warning count from ~1310 down to ~940,
with only 31 types of warnings in 148 files (down from 38 types in 167 files).

Tested on:
    MacOSX/64 10.11.5 (amazon) w/serial & parallel
    (h5committest forthcoming)

1 files changed, 169 insertions, 164 deletions

diff --git a/src/H5Dscatgath.c b/src/H5Dscatgath.c
index 7c1abca..55111f0 100644
--- a/src/H5Dscatgath.c
+++ b/src/H5Dscatgath.c
@@ -67,10 +67,13 @@ static herr_t H5D__compound_opt_write(size_t nelmts, const H5D_type_info_t *type
 /* Local Variables */
 /*******************/
 
-/* Declare a free list to manage sequences of size_t */
+/* Declare extern free list to manage the H5S_sel_iter_t struct */
+H5FL_EXTERN(H5S_sel_iter_t);
+
+/* Declare extern free list to manage sequences of size_t */
 H5FL_SEQ_EXTERN(size_t);
 
-/* Declare a free list to manage sequences of hsize_t */
+/* Declare extern free list to manage sequences of hsize_t */
 H5FL_SEQ_EXTERN(hsize_t);
 
 
@@ -97,17 +100,16 @@ H5D__scatter_file(const H5D_io_info_t *_io_info,
     const void *_buf)
 {
     H5D_io_info_t tmp_io_info;     /* Temporary I/O info object */
-    hsize_t _off[H5D_IO_VECTOR_SIZE];             /* Array to store sequence offsets */
     hsize_t *off = NULL;           /* Pointer to sequence offsets */
     hsize_t mem_off;               /* Offset in memory */
     size_t mem_curr_seq;           /* "Current sequence" in memory */
     size_t dset_curr_seq;          /* "Current sequence" in dataset */
-    size_t _len[H5D_IO_VECTOR_SIZE];              /* Array to store sequence lengths */
     size_t *len = NULL;            /* Array to store sequence lengths */
     size_t orig_mem_len, mem_len;  /* Length of sequence in memory */
-    size_t  nseq;                  /* Number of sequences generated */
-    size_t  nelem;                 /* Number of elements used in sequences */
-    herr_t  ret_value = SUCCEED;   /* Return value */
+    size_t nseq;                   /* Number of sequences generated */
+    size_t nelem;                  /* Number of elements used in sequences */
+    size_t vec_size;               /* Vector length */
+    herr_t ret_value = SUCCEED;    /* Return value */
 
     FUNC_ENTER_STATIC
 
@@ -124,21 +126,19 @@ H5D__scatter_file(const H5D_io_info_t *_io_info,
     tmp_io_info.u.wbuf = _buf;
 
     /* Allocate the vector I/O arrays */
-    if(tmp_io_info.dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE) {
-        if(NULL == (len = H5FL_SEQ_MALLOC(size_t, tmp_io_info.dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O length vector array")
-        if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, tmp_io_info.dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O offset vector array")
-    } /* end if */
-    else {
-        len = _len;
-        off = _off;
-    } /* end else */
+    if(tmp_io_info.dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE)
+        vec_size = tmp_io_info.dxpl_cache->vec_size;
+    else
+        vec_size = H5D_IO_VECTOR_SIZE;
+    if(NULL == (len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+    if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
 
     /* Loop until all elements are written */
     while(nelmts > 0) {
         /* Get list of sequences for selection to write */
-        if(H5S_SELECT_GET_SEQ_LIST(space, H5S_GET_SEQ_LIST_SORTED, iter, tmp_io_info.dxpl_cache->vec_size, nelmts, &nseq, &nelem, off, len) < 0)
+        if(H5S_SELECT_GET_SEQ_LIST(space, H5S_GET_SEQ_LIST_SORTED, iter, vec_size, nelmts, &nseq, &nelem, off, len) < 0)
             HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, FAIL, "sequence length generation failed")
 
         /* Reset the current sequence information */
@@ -160,9 +160,9 @@ H5D__scatter_file(const H5D_io_info_t *_io_info,
 
 done:
     /* Release resources, if allocated */
-    if(len && len != _len)
+    if(len)
         len = H5FL_SEQ_FREE(size_t, len);
-    if(off && off != _off)
+    if(off)
         off = H5FL_SEQ_FREE(hsize_t, off);
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -196,16 +196,15 @@ H5D__gather_file(const H5D_io_info_t *_io_info,
     void *_buf/*out*/)
 {
     H5D_io_info_t tmp_io_info;  /* Temporary I/O info object */
-    hsize_t _off[H5D_IO_VECTOR_SIZE];   /* Array to store sequence offsets */
     hsize_t *off = NULL;        /* Pointer to sequence offsets */
     hsize_t mem_off;            /* Offset in memory */
     size_t mem_curr_seq;        /* "Current sequence" in memory */
     size_t dset_curr_seq;       /* "Current sequence" in dataset */
-    size_t _len[H5D_IO_VECTOR_SIZE];    /* Array to store sequence lengths */
     size_t *len = NULL;         /* Pointer to sequence lengths */
     size_t orig_mem_len, mem_len;       /* Length of sequence in memory */
     size_t nseq;                /* Number of sequences generated */
     size_t nelem;               /* Number of elements used in sequences */
+    size_t vec_size;            /* Vector length */
     size_t ret_value = nelmts;  /* Return value */
 
     FUNC_ENTER_STATIC
@@ -225,21 +224,19 @@ H5D__gather_file(const H5D_io_info_t *_io_info,
     tmp_io_info.u.rbuf = _buf;
 
     /* Allocate the vector I/O arrays */
-    if(tmp_io_info.dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE) {
-        if(NULL == (len = H5FL_SEQ_MALLOC(size_t, tmp_io_info.dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "can't allocate I/O length vector array")
-        if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, tmp_io_info.dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "can't allocate I/O offset vector array")
-    } /* end if */
-    else {
-        len = _len;
-        off = _off;
-    } /* end else */
+    if(tmp_io_info.dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE)
+        vec_size = tmp_io_info.dxpl_cache->vec_size;
+    else
+        vec_size = H5D_IO_VECTOR_SIZE;
+    if(NULL == (len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, 0, "can't allocate I/O length vector array")
+    if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, 0, "can't allocate I/O offset vector array")
 
     /* Loop until all elements are read */
     while(nelmts > 0) {
         /* Get list of sequences for selection to read */
-        if(H5S_SELECT_GET_SEQ_LIST(space, H5S_GET_SEQ_LIST_SORTED, iter, tmp_io_info.dxpl_cache->vec_size, nelmts, &nseq, &nelem, off, len) < 0)
+        if(H5S_SELECT_GET_SEQ_LIST(space, H5S_GET_SEQ_LIST_SORTED, iter, vec_size, nelmts, &nseq, &nelem, off, len) < 0)
             HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, 0, "sequence length generation failed")
 
         /* Reset the current sequence information */
@@ -261,9 +258,9 @@ H5D__gather_file(const H5D_io_info_t *_io_info,
 
 done:
     /* Release resources, if allocated */
-    if(len && len != _len)
+    if(len)
         len = H5FL_SEQ_FREE(size_t, len);
-    if(off && off != _off)
+    if(off)
         off = H5FL_SEQ_FREE(hsize_t, off);
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -292,15 +289,14 @@ H5D__scatter_mem (const void *_tscat_buf, const H5S_t *space,
 {
     uint8_t *buf = (uint8_t *)_buf;   /* Get local copies for address arithmetic */
     const uint8_t *tscat_buf = (const uint8_t *)_tscat_buf;
-    hsize_t _off[H5D_IO_VECTOR_SIZE];          /* Array to store sequence offsets */
-    hsize_t *off = NULL;          /* Pointer to sequence offsets */
-    size_t _len[H5D_IO_VECTOR_SIZE];           /* Array to store sequence lengths */
-    size_t *len = NULL;           /* Pointer to sequence lengths */
+    hsize_t *off = NULL;        /* Pointer to sequence offsets */
+    size_t *len = NULL;         /* Pointer to sequence lengths */
     size_t curr_len;            /* Length of bytes left to process in sequence */
     size_t nseq;                /* Number of sequences generated */
     size_t curr_seq;            /* Current sequence being processed */
     size_t nelem;               /* Number of elements used in sequences */
-    herr_t ret_value = SUCCEED;   /* Number of elements scattered */
+    size_t vec_size;            /* Vector length */
+    herr_t ret_value = SUCCEED; /* Number of elements scattered */
 
     FUNC_ENTER_PACKAGE
 
@@ -312,21 +308,19 @@ H5D__scatter_mem (const void *_tscat_buf, const H5S_t *space,
     HDassert(buf);
 
     /* Allocate the vector I/O arrays */
-    if(dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE) {
-        if(NULL == (len = H5FL_SEQ_MALLOC(size_t, dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O length vector array")
-        if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O offset vector array")
-    } /* end if */
-    else {
-        len = _len;
-        off = _off;
-    } /* end else */
+    if(dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE)
+        vec_size = dxpl_cache->vec_size;
+    else
+        vec_size = H5D_IO_VECTOR_SIZE;
+    if(NULL == (len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+    if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
 
     /* Loop until all elements are written */
     while(nelmts > 0) {
         /* Get list of sequences for selection to write */
-        if(H5S_SELECT_GET_SEQ_LIST(space, 0, iter, dxpl_cache->vec_size, nelmts, &nseq, &nelem, off, len) < 0)
+        if(H5S_SELECT_GET_SEQ_LIST(space, 0, iter, vec_size, nelmts, &nseq, &nelem, off, len) < 0)
             HGOTO_ERROR (H5E_INTERNAL, H5E_UNSUPPORTED, 0, "sequence length generation failed")
 
         /* Loop, while sequences left to process */
@@ -346,9 +340,9 @@ H5D__scatter_mem (const void *_tscat_buf, const H5S_t *space,
 
 done:
     /* Release resources, if allocated */
-    if(len && len != _len)
+    if(len)
         len = H5FL_SEQ_FREE(size_t, len);
-    if(off && off != _off)
+    if(off)
         off = H5FL_SEQ_FREE(hsize_t, off);
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -379,15 +373,14 @@ H5D__gather_mem(const void *_buf, const H5S_t *space,
 {
     const uint8_t *buf = (const uint8_t *)_buf;   /* Get local copies for address arithmetic */
     uint8_t *tgath_buf = (uint8_t *)_tgath_buf;
-    hsize_t _off[H5D_IO_VECTOR_SIZE];          /* Array to store sequence offsets */
     hsize_t *off = NULL;          /* Pointer to sequence offsets */
-    size_t _len[H5D_IO_VECTOR_SIZE];           /* Array to store sequence lengths */
-    size_t *len = NULL;           /* Pointer to sequence lengths */
+    size_t *len = NULL;         /* Pointer to sequence lengths */
     size_t curr_len;            /* Length of bytes left to process in sequence */
     size_t nseq;                /* Number of sequences generated */
     size_t curr_seq;            /* Current sequence being processed */
     size_t nelem;               /* Number of elements used in sequences */
-    size_t ret_value = nelmts;    /* Number of elements gathered */
+    size_t vec_size;            /* Vector length */
+    size_t ret_value = nelmts;  /* Number of elements gathered */
 
     FUNC_ENTER_STATIC
 
@@ -399,21 +392,19 @@ H5D__gather_mem(const void *_buf, const H5S_t *space,
     HDassert(tgath_buf);
 
     /* Allocate the vector I/O arrays */
-    if(dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE) {
-        if(NULL == (len = H5FL_SEQ_MALLOC(size_t, dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "can't allocate I/O length vector array")
-        if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "can't allocate I/O offset vector array")
-    } /* end if */
-    else {
-        len = _len;
-        off = _off;
-    } /* end else */
+    if(dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE)
+        vec_size = dxpl_cache->vec_size;
+    else
+        vec_size = H5D_IO_VECTOR_SIZE;
+    if(NULL == (len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, 0, "can't allocate I/O length vector array")
+    if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, 0, "can't allocate I/O offset vector array")
 
     /* Loop until all elements are written */
     while(nelmts > 0) {
         /* Get list of sequences for selection to write */
-        if(H5S_SELECT_GET_SEQ_LIST(space, 0, iter, dxpl_cache->vec_size, nelmts, &nseq, &nelem, off, len) < 0)
+        if(H5S_SELECT_GET_SEQ_LIST(space, 0, iter, vec_size, nelmts, &nseq, &nelem, off, len) < 0)
             HGOTO_ERROR (H5E_INTERNAL, H5E_UNSUPPORTED, 0, "sequence length generation failed")
 
         /* Loop, while sequences left to process */
@@ -433,9 +424,9 @@ H5D__gather_mem(const void *_buf, const H5S_t *space,
 
 done:
     /* Release resources, if allocated */
-    if(len && len != _len)
+    if(len)
         len = H5FL_SEQ_FREE(size_t, len);
-    if(off && off != _off)
+    if(off)
         off = H5FL_SEQ_FREE(hsize_t, off);
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -460,15 +451,15 @@ H5D__scatgath_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_inf
 {
     const H5D_dxpl_cache_t *dxpl_cache = io_info->dxpl_cache;     /* Local pointer to dataset transfer info */
     void        *buf = io_info->u.rbuf; /* Local pointer to application buffer */
-    H5S_sel_iter_t mem_iter;            /*memory selection iteration info*/
-    hbool_t	mem_iter_init = FALSE;	/*memory selection iteration info has been initialized */
-    H5S_sel_iter_t bkg_iter;            /*background iteration info*/
-    hbool_t	bkg_iter_init = FALSE;	/*background iteration info has been initialized */
-    H5S_sel_iter_t file_iter;           /*file selection iteration info*/
-    hbool_t	file_iter_init = FALSE;	/*file selection iteration info has been initialized */
-    hsize_t	smine_start;		/*strip mine start loc	*/
-    size_t	smine_nelmts;		/*elements per strip	*/
-    herr_t	ret_value = SUCCEED;	/*return value		*/
+    H5S_sel_iter_t *mem_iter = NULL;    /* Memory selection iteration info*/
+    hbool_t	mem_iter_init = FALSE;	/* Memory selection iteration info has been initialized */
+    H5S_sel_iter_t *bkg_iter = NULL;    /* Background iteration info*/
+    hbool_t	bkg_iter_init = FALSE;	/* Background iteration info has been initialized */
+    H5S_sel_iter_t *file_iter = NULL;   /* File selection iteration info*/
+    hbool_t	file_iter_init = FALSE;	/* File selection iteration info has been initialized */
+    hsize_t	smine_start;		/* Strip mine start loc	*/
+    size_t	smine_nelmts;		/* Elements per strip	*/
+    herr_t	ret_value = SUCCEED;	/* Return value		*/
 
     FUNC_ENTER_PACKAGE
 
@@ -483,14 +474,22 @@ H5D__scatgath_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_inf
     if(nelmts == 0)
         HGOTO_DONE(SUCCEED)
 
+    /* Allocate the iterators */
+    if(NULL == (mem_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate memory iterator")
+    if(NULL == (bkg_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate background iterator")
+    if(NULL == (file_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate file iterator")
+
     /* Figure out the strip mine size. */
-    if(H5S_select_iter_init(&file_iter, file_space, type_info->src_type_size) < 0)
+    if(H5S_select_iter_init(file_iter, file_space, type_info->src_type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize file selection information")
     file_iter_init = TRUE;	/*file selection iteration info has been initialized */
-    if(H5S_select_iter_init(&mem_iter, mem_space, type_info->dst_type_size) < 0)
+    if(H5S_select_iter_init(mem_iter, mem_space, type_info->dst_type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize memory selection information")
     mem_iter_init = TRUE;	/*file selection iteration info has been initialized */
-    if(H5S_select_iter_init(&bkg_iter, mem_space, type_info->dst_type_size) < 0)
+    if(H5S_select_iter_init(bkg_iter, mem_space, type_info->dst_type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize background selection information")
     bkg_iter_init = TRUE;	/*file selection iteration info has been initialized */
 
@@ -499,7 +498,7 @@ H5D__scatgath_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_inf
         size_t n;               /* Elements operated on */
 
         /* Go figure out how many elements to read from the file */
-        HDassert(H5S_SELECT_ITER_NELMTS(&file_iter) == (nelmts - smine_start));
+        HDassert(H5S_SELECT_ITER_NELMTS(file_iter) == (nelmts - smine_start));
         smine_nelmts = (size_t)MIN(type_info->request_nelmts, (nelmts - smine_start));
 
         /*
@@ -511,8 +510,7 @@ H5D__scatgath_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_inf
 	/*
          * Gather data
          */
-        n = H5D__gather_file(io_info, file_space, &file_iter, smine_nelmts,
-                type_info->tconv_buf/*out*/);
+        n = H5D__gather_file(io_info, file_space, file_iter, smine_nelmts, type_info->tconv_buf/*out*/);
 	if(n != smine_nelmts)
             HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "file gather failed")
 
@@ -521,14 +519,12 @@ H5D__scatgath_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_inf
          * bypass the rest of steps.
          */
         if(type_info->cmpd_subset && H5T_SUBSET_FALSE != type_info->cmpd_subset->subset) {
-            if(H5D__compound_opt_read(smine_nelmts, mem_space, &mem_iter, dxpl_cache,
-                    type_info, buf /*out*/) < 0)
+            if(H5D__compound_opt_read(smine_nelmts, mem_space, mem_iter, dxpl_cache, type_info, buf /*out*/) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "datatype conversion failed")
         } /* end if */
         else {
             if(H5T_BKG_YES == type_info->need_bkg) {
-                n = H5D__gather_mem(buf, mem_space, &bkg_iter, smine_nelmts,
-                        dxpl_cache, type_info->bkg_buf/*out*/);
+                n = H5D__gather_mem(buf, mem_space, bkg_iter, smine_nelmts, dxpl_cache, type_info->bkg_buf/*out*/);
                 if(n != smine_nelmts)
                     HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "mem gather failed")
             } /* end if */
@@ -549,26 +545,25 @@ H5D__scatgath_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_inf
             /*
              * Scatter the data into memory.
              */
-            if(H5D__scatter_mem(type_info->tconv_buf, mem_space, &mem_iter,
-                    smine_nelmts, dxpl_cache, buf/*out*/) < 0)
+            if(H5D__scatter_mem(type_info->tconv_buf, mem_space, mem_iter, smine_nelmts, dxpl_cache, buf/*out*/) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "scatter failed")
         } /* end else */
     } /* end for */
 
 done:
     /* Release selection iterators */
-    if(file_iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&file_iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
-    if(mem_iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&mem_iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
-    if(bkg_iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&bkg_iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
+    if(file_iter_init && H5S_SELECT_ITER_RELEASE(file_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(file_iter)
+        file_iter = H5FL_FREE(H5S_sel_iter_t, file_iter);
+    if(mem_iter_init && H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(mem_iter)
+        mem_iter = H5FL_FREE(H5S_sel_iter_t, mem_iter);
+    if(bkg_iter_init && H5S_SELECT_ITER_RELEASE(bkg_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(bkg_iter)
+        bkg_iter = H5FL_FREE(H5S_sel_iter_t, bkg_iter);
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__scatgath_read() */
@@ -592,15 +587,15 @@ H5D__scatgath_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_in
 {
     const H5D_dxpl_cache_t *dxpl_cache = io_info->dxpl_cache;     /* Local pointer to dataset transfer info */
     const void  *buf = io_info->u.wbuf; /* Local pointer to application buffer */
-    H5S_sel_iter_t mem_iter;            /*memory selection iteration info*/
-    hbool_t	mem_iter_init = FALSE;	/*memory selection iteration info has been initialized */
-    H5S_sel_iter_t bkg_iter;            /*background iteration info*/
-    hbool_t	bkg_iter_init = FALSE;	/*background iteration info has been initialized */
-    H5S_sel_iter_t file_iter;           /*file selection iteration info*/
-    hbool_t	file_iter_init = FALSE;	/*file selection iteration info has been initialized */
-    hsize_t	smine_start;		/*strip mine start loc	*/
-    size_t	smine_nelmts;		/*elements per strip	*/
-    herr_t	ret_value = SUCCEED;	/*return value		*/
+    H5S_sel_iter_t *mem_iter = NULL;    /* Memory selection iteration info*/
+    hbool_t	mem_iter_init = FALSE;	/* Memory selection iteration info has been initialized */
+    H5S_sel_iter_t *bkg_iter = NULL;    /* Background iteration info*/
+    hbool_t	bkg_iter_init = FALSE;	/* Background iteration info has been initialized */
+    H5S_sel_iter_t *file_iter = NULL;   /* File selection iteration info*/
+    hbool_t	file_iter_init = FALSE;	/* File selection iteration info has been initialized */
+    hsize_t	smine_start;		/* Strip mine start loc	*/
+    size_t	smine_nelmts;		/* Elements per strip	*/
+    herr_t	ret_value = SUCCEED;	/* Return value		*/
 
     FUNC_ENTER_PACKAGE
 
@@ -615,14 +610,22 @@ H5D__scatgath_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_in
     if(nelmts == 0)
         HGOTO_DONE(SUCCEED)
 
+    /* Allocate the iterators */
+    if(NULL == (mem_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate memory iterator")
+    if(NULL == (bkg_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate background iterator")
+    if(NULL == (file_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate file iterator")
+
     /* Figure out the strip mine size. */
-    if(H5S_select_iter_init(&file_iter, file_space, type_info->dst_type_size) < 0)
+    if(H5S_select_iter_init(file_iter, file_space, type_info->dst_type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize file selection information")
     file_iter_init = TRUE;	/*file selection iteration info has been initialized */
-    if(H5S_select_iter_init(&mem_iter, mem_space, type_info->src_type_size) < 0)
+    if(H5S_select_iter_init(mem_iter, mem_space, type_info->src_type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize memory selection information")
     mem_iter_init = TRUE;	/*file selection iteration info has been initialized */
-    if(H5S_select_iter_init(&bkg_iter, file_space, type_info->dst_type_size) < 0)
+    if(H5S_select_iter_init(bkg_iter, file_space, type_info->dst_type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize background selection information")
     bkg_iter_init = TRUE;	/*file selection iteration info has been initialized */
 
@@ -631,7 +634,7 @@ H5D__scatgath_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_in
         size_t n;               /* Elements operated on */
 
         /* Go figure out how many elements to read from the file */
-        HDassert(H5S_SELECT_ITER_NELMTS(&file_iter) == (nelmts - smine_start));
+        HDassert(H5S_SELECT_ITER_NELMTS(file_iter) == (nelmts - smine_start));
         smine_nelmts = (size_t)MIN(type_info->request_nelmts, (nelmts - smine_start));
 
         /*
@@ -639,8 +642,7 @@ H5D__scatgath_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_in
          * buffer. Also gather data from the file into the background buffer
          * if necessary.
          */
-        n = H5D__gather_mem(buf, mem_space, &mem_iter, smine_nelmts,
-                dxpl_cache, type_info->tconv_buf/*out*/);
+        n = H5D__gather_mem(buf, mem_space, mem_iter, smine_nelmts, dxpl_cache, type_info->tconv_buf/*out*/);
         if(n != smine_nelmts)
             HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "mem gather failed")
 
@@ -657,8 +659,7 @@ H5D__scatgath_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_in
         } /* end if */
         else {
             if(H5T_BKG_YES == type_info->need_bkg) {
-                n = H5D__gather_file(io_info, file_space, &bkg_iter, smine_nelmts,
-                        type_info->bkg_buf/*out*/);
+                n = H5D__gather_file(io_info, file_space, bkg_iter, smine_nelmts, type_info->bkg_buf/*out*/);
                 if(n != smine_nelmts)
                     HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "file gather failed")
             } /* end if */
@@ -681,25 +682,24 @@ H5D__scatgath_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_in
         /*
          * Scatter the data out to the file.
          */
-        if(H5D__scatter_file(io_info, file_space, &file_iter, smine_nelmts,
-                type_info->tconv_buf) < 0)
+        if(H5D__scatter_file(io_info, file_space, file_iter, smine_nelmts, type_info->tconv_buf) < 0)
             HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "scatter failed")
     } /* end for */
 
 done:
     /* Release selection iterators */
-    if(file_iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&file_iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
-    if(mem_iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&mem_iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
-    if(bkg_iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&bkg_iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
+    if(file_iter_init && H5S_SELECT_ITER_RELEASE(file_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(file_iter)
+        file_iter = H5FL_FREE(H5S_sel_iter_t, file_iter);
+    if(mem_iter_init && H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(mem_iter)
+        mem_iter = H5FL_FREE(H5S_sel_iter_t, mem_iter);
+    if(bkg_iter_init && H5S_SELECT_ITER_RELEASE(bkg_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(bkg_iter)
+        bkg_iter = H5FL_FREE(H5S_sel_iter_t, bkg_iter);
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__scatgath_write() */
@@ -744,12 +744,11 @@ H5D__compound_opt_read(size_t nelmts, const H5S_t *space,
 {
     uint8_t    *ubuf = (uint8_t *)user_buf;     /* Cast for pointer arithmetic	*/
     uint8_t    *xdbuf;                          /* Pointer into dataset buffer */
-    hsize_t    _off[H5D_IO_VECTOR_SIZE];        /* Array to store sequence offsets */
     hsize_t    *off = NULL;                     /* Pointer to sequence offsets */
-    size_t     _len[H5D_IO_VECTOR_SIZE];        /* Array to store sequence lengths */
     size_t     *len = NULL;                     /* Pointer to sequence lengths */
     size_t     src_stride, dst_stride, copy_size;
-    herr_t     ret_value = SUCCEED;	       /*return value		*/
+    size_t     vec_size;                        /* Vector length */
+    herr_t     ret_value = SUCCEED;	        /* Return value		*/
 
     FUNC_ENTER_STATIC
 
@@ -765,16 +764,14 @@ H5D__compound_opt_read(size_t nelmts, const H5S_t *space,
     HDassert(user_buf);
 
     /* Allocate the vector I/O arrays */
-    if(dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE) {
-        if(NULL == (len = H5FL_SEQ_MALLOC(size_t, dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O length vector array")
-        if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, dxpl_cache->vec_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O offset vector array")
-    } /* end if */
-    else {
-        len = _len;
-        off = _off;
-    } /* end else */
+    if(dxpl_cache->vec_size > H5D_IO_VECTOR_SIZE)
+        vec_size = dxpl_cache->vec_size;
+    else
+        vec_size = H5D_IO_VECTOR_SIZE;
+    if(NULL == (len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+    if(NULL == (off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
 
     /* Get source & destination strides */
     src_stride = type_info->src_type_size;
@@ -791,7 +788,7 @@ H5D__compound_opt_read(size_t nelmts, const H5S_t *space,
         size_t     elmtno;		/* Element counter */
 
         /* Get list of sequences for selection to write */
-        if(H5S_SELECT_GET_SEQ_LIST(space, 0, iter, dxpl_cache->vec_size, nelmts, &nseq, &elmtno, off, len) < 0)
+        if(H5S_SELECT_GET_SEQ_LIST(space, 0, iter, vec_size, nelmts, &nseq, &elmtno, off, len) < 0)
             HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, 0, "sequence length generation failed")
 
         /* Loop, while sequences left to process */
@@ -827,9 +824,9 @@ H5D__compound_opt_read(size_t nelmts, const H5S_t *space,
 
 done:
     /* Release resources, if allocated */
-    if(len && len != _len)
+    if(len)
         len = H5FL_SEQ_FREE(size_t, len);
-    if(off && off != _off)
+    if(off)
         off = H5FL_SEQ_FREE(hsize_t, off);
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -923,7 +920,7 @@ H5Dscatter(H5D_scatter_func_t op, void *op_data, hid_t type_id,
 {
     H5T_t *type;                /* Datatype */
     H5S_t *dst_space;           /* Dataspace */
-    H5S_sel_iter_t iter;        /* Selection iteration info*/
+    H5S_sel_iter_t *iter = NULL; /* Selection iteration info*/
     hbool_t iter_init = FALSE;  /* Selection iteration info has been initialized */
     const void *src_buf = NULL; /* Source (contiguous) data buffer */
     size_t src_buf_nbytes = 0;  /* Size of src_buf */
@@ -959,8 +956,12 @@ H5Dscatter(H5D_scatter_func_t op, void *op_data, hid_t type_id,
     if((nelmts = (hssize_t)H5S_GET_SELECT_NPOINTS(dst_space)) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "unable to get number of elements in selection")
 
+    /* Allocate the selection iterator */
+    if(NULL == (iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate selection iterator")
+
     /* Initialize selection iterator */
-    if(H5S_select_iter_init(&iter, dst_space, type_size) < 0)
+    if(H5S_select_iter_init(iter, dst_space, type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize selection iterator information")
     iter_init = TRUE;
 
@@ -984,7 +985,7 @@ H5Dscatter(H5D_scatter_func_t op, void *op_data, hid_t type_id,
             HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "callback returned more elements than in selection")
 
         /* Scatter data */
-        if(H5D__scatter_mem(src_buf, dst_space, &iter, nelmts_scatter, dxpl_cache, dst_buf) < 0)
+        if(H5D__scatter_mem(src_buf, dst_space, iter, nelmts_scatter, dxpl_cache, dst_buf) < 0)
             HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "scatter failed")
 
         nelmts -= (hssize_t)nelmts_scatter;
@@ -992,10 +993,10 @@ H5Dscatter(H5D_scatter_func_t op, void *op_data, hid_t type_id,
 
 done:
     /* Release selection iterator */
-    if(iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
+    if(iter_init && H5S_SELECT_ITER_RELEASE(iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(iter)
+        iter = H5FL_FREE(H5S_sel_iter_t, iter);
 
     FUNC_LEAVE_API(ret_value)
 }   /* H5Dscatter() */
@@ -1023,7 +1024,7 @@ H5Dgather(hid_t src_space_id, const void *src_buf, hid_t type_id,
 {
     H5T_t *type;                /* Datatype */
     H5S_t *src_space;           /* Dataspace */
-    H5S_sel_iter_t iter;        /* Selection iteration info*/
+    H5S_sel_iter_t *iter = NULL; /* Selection iteration info*/
     hbool_t iter_init = FALSE;  /* Selection iteration info has been initialized */
     size_t type_size;           /* Datatype element size */
     hssize_t nelmts;            /* Number of remaining elements in selection */
@@ -1071,15 +1072,19 @@ H5Dgather(hid_t src_space_id, const void *src_buf, hid_t type_id,
     if(((size_t)nelmts > dst_buf_nelmts) && (op == NULL))
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no callback supplied and destination buffer too small")
 
+    /* Allocate the selection iterator */
+    if(NULL == (iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate selection iterator")
+
     /* Initialize selection iterator */
-    if(H5S_select_iter_init(&iter, src_space, type_size) < 0)
+    if(H5S_select_iter_init(iter, src_space, type_size) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize selection iterator information")
     iter_init = TRUE;
 
     /* Loop until all data has been scattered */
     while(nelmts > 0) {
         /* Gather data */
-        if(0 == (nelmts_gathered = H5D__gather_mem(src_buf, src_space, &iter, MIN(dst_buf_nelmts, (size_t)nelmts), dxpl_cache, dst_buf)))
+        if(0 == (nelmts_gathered = H5D__gather_mem(src_buf, src_space, iter, MIN(dst_buf_nelmts, (size_t)nelmts), dxpl_cache, dst_buf)))
             HGOTO_ERROR(H5E_IO, H5E_CANTCOPY, FAIL, "gather failed")
         HDassert(nelmts_gathered == MIN(dst_buf_nelmts, (size_t)nelmts));
 
@@ -1093,10 +1098,10 @@ H5Dgather(hid_t src_space_id, const void *src_buf, hid_t type_id,
 
 done:
     /* Release selection iterator */
-    if(iter_init) {
-        if(H5S_SELECT_ITER_RELEASE(&iter) < 0)
-            HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
-    } /* end if */
+    if(iter_init && H5S_SELECT_ITER_RELEASE(iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release selection iterator")
+    if(iter)
+        iter = H5FL_FREE(H5S_sel_iter_t, iter);
 
     FUNC_LEAVE_API(ret_value)
 }   /* H5Dgather() */