[svn-r9366]

Purpose:  feature change

Description:  Prevent creating datatype of size 0.


Platforms tested:  fuss(simple change)

3 files changed, 19 insertions, 8 deletions

diff --git a/release_docs/RELEASE.txt b/release_docs/RELEASE.txt
index cfa6f5f..2c29bb8 100644
--- a/release_docs/RELEASE.txt
+++ b/release_docs/RELEASE.txt
@@ -52,8 +52,8 @@ New Features
     --------
         - Compound datatype has been enhanced with a new feature of size 
             adjustment.  The size can be increased and decreased(without
-            cutting the last member).  No API change is involved.  SLU - 
-            2004/10/1
+            cutting the last member) as long as it doesn't go down to zero.  
+            No API change is involved.  SLU - 2004/10/1
         - Put back 6 old error API functions to be backward compatible with
             version 1.6.  They are H5Epush, H5Eprint, H5Ewalk, H5Eclear,
             H5Eset_auto, H5Eget_auto.  Their new equivalent functions are
diff --git a/src/H5T.c b/src/H5T.c
index d901b98..9662983 100644
--- a/src/H5T.c
+++ b/src/H5T.c
@@ -1453,8 +1453,8 @@ H5Tcreate(H5T_class_t type, size_t size)
     FUNC_ENTER_API(H5Tcreate, FAIL);
     H5TRACE2("i","Ttz",type,size);
 
-    /* check args. We start to support size adjustment for compound type. */
-    if (size == 0 && type != H5T_COMPOUND)
+    /* check args */
+    if (size == 0)
 	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid size");
 
     /* create the type */
@@ -2024,6 +2024,8 @@ H5Tset_size(hid_t type_id, size_t size)
 	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not allowed after members are defined");
     if (H5T_REFERENCE==dt->shared->type)
 	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not defined for this datatype");
+    if (size==0)
+	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "can't adjust size to 0");
 
     /* Do the work */
     if (H5T_set_size(dt, size)<0)
diff --git a/test/dtypes.c b/test/dtypes.c
index e07e200..6d67bf0 100644
--- a/test/dtypes.c
+++ b/test/dtypes.c
@@ -2098,8 +2098,12 @@ test_compound_12(void)
 
     TESTING("adjust size of compound data types");
 
-    /* Create the empty compound type */
-    if ((complex_id = H5Tcreate(H5T_COMPOUND, 0))<0) goto error;
+    /* Create a compound type of minimal size */
+    if ((complex_id = H5Tcreate(H5T_COMPOUND, 1))<0) goto error;
+    
+    /* Verify the size */
+    if((new_size=H5Tget_size(complex_id))<0) goto error; 
+    if(new_size!=1) goto error;
 
     /* Add a couple fields and adjust the size */
     offset = size;
@@ -2128,9 +2132,14 @@ test_compound_12(void)
     /* Tries to cut last member.  Supposed to fail. */
     size--;
     H5E_BEGIN_TRY {
-        H5Tset_size(complex_id, size);
+        ret = H5Tset_size(complex_id, size);
     } H5E_END_TRY;  
-    
+    if(ret>=0) {
+        H5_FAILED();
+        puts("  Tries to cut off the last member. Should have failed.");
+        goto error;
+    }
+
     if (H5Tclose (complex_id)<0) goto error;
     PASSED();
     return 0;