[svn-r11311] Purpose: New features.

Description:  Added 2 new configure options, --enable-exception and --enable-accuracy.

--enable-exception lets the library check whether user's exception handling
functions are present during compiler data conversions and use them if they are.
When it's disabled, this step is skipped to improve conversion speed.  This
step isn't implemented yet for soft conversions because there would be little
gain in speed.

--enable-accuracy guarantees data accuracy during data conversions.  It means
the library will choose compiler conversions only if the accurate data is
secured.  Otherwise, the library will go for the library's own conversions.  If
this option is disabled, the library uses compiler conversions in favor of
their speed as long as they work even if data can be incorrect.


Platforms tested: h5committest and fuss.  Some systems may fail after this
checkin.

4 files changed, 303 insertions, 147 deletions

diff --git a/src/H5T.c b/src/H5T.c
index 1894f33..7e4754e 100644
--- a/src/H5T.c
+++ b/src/H5T.c
@@ -1001,16 +1001,16 @@ H5T_init_interface(void)
      */
 
     /* floating point */
-#if H5_CONVERT_DENORMAL_FLOAT
+#if FP_FP
     status |= H5T_register(H5T_PERS_HARD, "flt_dbl", native_float, native_double, H5T_conv_float_double, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_flt", native_double, native_float, H5T_conv_double_float, H5AC_dxpl_id);
-#if H5_SIZEOF_LONG_DOUBLE !=0
+#endif /*FP_FP*/
+#if FP_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "flt_ldbl", native_float, native_ldouble, H5T_conv_float_ldouble, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_ldbl", native_double, native_ldouble, H5T_conv_double_ldouble, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "ldbl_flt", native_ldouble, native_float, H5T_conv_ldouble_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "ldbl_dbl", native_ldouble, native_double, H5T_conv_ldouble_double, H5AC_dxpl_id);
-#endif
-#endif /*H5_CONVERT_DENORMAL_FLOAT*/
+#endif /*FP_LDOUBLE*/
 
     /* from long_long */
     status |= H5T_register(H5T_PERS_HARD, "llong_ullong", native_llong, native_ullong, H5T_conv_llong_ullong, H5AC_dxpl_id);
@@ -1115,149 +1115,149 @@ H5T_init_interface(void)
     /* From char to floats */
     status |= H5T_register(H5T_PERS_HARD, "schar_flt", native_schar, native_float, H5T_conv_schar_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "schar_dbl", native_schar, native_double, H5T_conv_schar_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "schar_ldbl", native_schar, native_ldouble, H5T_conv_schar_ldouble, H5AC_dxpl_id);
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
     /* From unsigned char to floats */
     status |= H5T_register(H5T_PERS_HARD, "uchar_flt", native_uchar, native_float, H5T_conv_uchar_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "uchar_dbl", native_uchar, native_double, H5T_conv_uchar_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "uchar_ldbl", native_uchar, native_ldouble, H5T_conv_uchar_ldouble, H5AC_dxpl_id);
-#endif /*H5_SW_INTEGER_TO_LDOUBLE_WORKS*/
+#endif /* INTEGER_LDOUBLE */
 
     /* From short to floats */
     status |= H5T_register(H5T_PERS_HARD, "short_flt", native_short, native_float, H5T_conv_short_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "short_dbl", native_short, native_double, H5T_conv_short_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "short_ldbl", native_short, native_ldouble, H5T_conv_short_ldouble, H5AC_dxpl_id);
-#endif /*H5_SW_INTEGER_TO_LDOUBLE_WORKS*/
+#endif /* INTEGER_LDOUBLE */
 
     /* From unsigned short to floats */
     status |= H5T_register(H5T_PERS_HARD, "ushort_flt", native_ushort, native_float, H5T_conv_ushort_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "ushort_dbl", native_ushort, native_double, H5T_conv_ushort_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "ushort_ldbl", native_ushort, native_ldouble, H5T_conv_ushort_ldouble, H5AC_dxpl_id);
-#endif /*H5_SW_INTEGER_TO_LDOUBLE_WORKS*/
+#endif /* INTEGER_LDOUBLE */
 
     /* From int to floats */
     status |= H5T_register(H5T_PERS_HARD, "int_flt", native_int, native_float, H5T_conv_int_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "int_dbl", native_int, native_double, H5T_conv_int_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "int_ldbl", native_int, native_ldouble, H5T_conv_int_ldouble, H5AC_dxpl_id);
-#endif /*H5_SW_INTEGER_TO_LDOUBLE_WORKS*/
+#endif /* INTEGER_LDOUBLE */
 
     /* From unsigned int to floats */
     status |= H5T_register(H5T_PERS_HARD, "uint_flt", native_uint, native_float, H5T_conv_uint_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "uint_dbl", native_uint, native_double, H5T_conv_uint_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "uint_ldbl", native_uint, native_ldouble, H5T_conv_uint_ldouble, H5AC_dxpl_id);
-#endif /*H5_SW_INTEGER_TO_LDOUBLE_WORKS*/
+#endif /* INTEGER_LDOUBLE */
 
     /* From long to floats */
     status |= H5T_register(H5T_PERS_HARD, "long_flt", native_long, native_float, H5T_conv_long_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "long_dbl", native_long, native_double, H5T_conv_long_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "long_ldbl", native_long, native_ldouble, H5T_conv_long_ldouble, H5AC_dxpl_id);
-#endif /*H5_SW_INTEGER_TO_LDOUBLE_WORKS*/
+#endif /* INTEGER_LDOUBLE */
 
     /* From unsigned long to floats */
-#if H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS
+#if ULONG_FP
     status |= H5T_register(H5T_PERS_HARD, "ulong_flt", native_ulong, native_float, H5T_conv_ulong_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "ulong_dbl", native_ulong, native_double, H5T_conv_ulong_double, H5AC_dxpl_id);
-#endif /* H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS */
-#if H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS && H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#endif /* ULONG_FP */
+#if ULONG_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "ulong_ldbl", native_ulong, native_ldouble, H5T_conv_ulong_ldouble, H5AC_dxpl_id);
-#endif /* H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS && H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* ULONG_LDOUBLE */
 
     /* From long long to floats */
     status |= H5T_register(H5T_PERS_HARD, "llong_flt", native_llong, native_float, H5T_conv_llong_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "llong_dbl", native_llong, native_double, H5T_conv_llong_double, H5AC_dxpl_id);
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "llong_ldbl", native_llong, native_ldouble, H5T_conv_llong_ldouble, H5AC_dxpl_id);
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
     /* From unsigned long long to floats */
-#if H5_ULLONG_TO_FP_CAST_WORKS && H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS
+#if ULLONG_FP
     status |= H5T_register(H5T_PERS_HARD, "ullong_flt", native_ullong, native_float, H5T_conv_ullong_float, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "ullong_dbl", native_ullong, native_double, H5T_conv_ullong_double, H5AC_dxpl_id);
-#if H5_ULLONG_TO_LDOUBLE_PRECISION_WORKS
+#endif /* ULLONG_FP */
+#if ULLONG_LDOUBLE
     status |= H5T_register(H5T_PERS_HARD, "ullong_ldbl", native_ullong, native_ldouble, H5T_conv_ullong_ldouble, H5AC_dxpl_id);
-#endif /* H5_ULLONG_TO_LDOUBLE_PRECISION_WORKS */
-#endif /* H5_ULLONG_TO_FP_CAST_WORKS && H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS */
+#endif /* ULLONG_LDOUBLE */
 
     /* From floats to char */
     status |= H5T_register(H5T_PERS_HARD, "flt_schar", native_float, native_schar, H5T_conv_float_schar, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_schar", native_double, native_schar, H5T_conv_double_schar, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_schar", native_ldouble, native_schar, H5T_conv_ldouble_schar, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to unsigned char */
     status |= H5T_register(H5T_PERS_HARD, "flt_uchar", native_float, native_uchar, H5T_conv_float_uchar, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_uchar", native_double, native_uchar, H5T_conv_double_uchar, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_uchar", native_ldouble, native_uchar, H5T_conv_ldouble_uchar, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to short */
     status |= H5T_register(H5T_PERS_HARD, "flt_short", native_float, native_short, H5T_conv_float_short, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_short", native_double, native_short, H5T_conv_double_short, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_short", native_ldouble, native_short, H5T_conv_ldouble_short, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to unsigned short */
     status |= H5T_register(H5T_PERS_HARD, "flt_ushort", native_float, native_ushort, H5T_conv_float_ushort, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_ushort", native_double, native_ushort, H5T_conv_double_ushort, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_ushort", native_ldouble, native_ushort, H5T_conv_ldouble_ushort, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to int */
     status |= H5T_register(H5T_PERS_HARD, "flt_int", native_float, native_int, H5T_conv_float_int, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_int", native_double, native_int, H5T_conv_double_int, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_int", native_ldouble, native_int, H5T_conv_ldouble_int, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to unsigned int */
     status |= H5T_register(H5T_PERS_HARD, "flt_uint", native_float, native_uint, H5T_conv_float_uint, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_uint", native_double, native_uint, H5T_conv_double_uint, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS && H5_CV_LDOUBLE_TO_UINT_WORKS
+#if LDOUBLE_UINT
     status |= H5T_register(H5T_PERS_HARD, "ldbl_uint", native_ldouble, native_uint, H5T_conv_ldouble_uint, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS && H5_CV_LDOUBLE_TO_UINT_WORKS */
+#endif /* LDOUBLE_UINT */
 
     status |= H5T_register(H5T_PERS_HARD, "flt_long", native_float, native_long, H5T_conv_float_long, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_long", native_double, native_long, H5T_conv_double_long, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_long", native_ldouble, native_long, H5T_conv_ldouble_long, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to unsigned long */
     status |= H5T_register(H5T_PERS_HARD, "flt_ulong", native_float, native_ulong, H5T_conv_float_ulong, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_ulong", native_double, native_ulong, H5T_conv_double_ulong, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
     status |= H5T_register(H5T_PERS_HARD, "ldbl_ulong", native_ldouble, native_ulong, H5T_conv_ldouble_ulong, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
     /* From floats to long long */
-#ifndef H5_HW_FP_TO_LLONG_NOT_WORKS
+#if FP_LLONG
     status |= H5T_register(H5T_PERS_HARD, "flt_llong", native_float, native_llong, H5T_conv_float_llong, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_llong", native_double, native_llong, H5T_conv_double_llong, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#endif /* FP_LLONG */
+#if LDOUBLE_LLONG
     status |= H5T_register(H5T_PERS_HARD, "ldbl_llong", native_ldouble, native_llong, H5T_conv_ldouble_llong, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
-#endif /* !H5_HW_FP_TO_LLONG_NOT_WORKS */
+#endif /* LDOUBLE_LLONG */
 
     /* From floats to unsigned long long */
-#if H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM
+#if FP_ULLONG
     status |= H5T_register(H5T_PERS_HARD, "flt_ullong", native_float, native_ullong, H5T_conv_float_ullong, H5AC_dxpl_id);
     status |= H5T_register(H5T_PERS_HARD, "dbl_ullong", native_double, native_ullong, H5T_conv_double_ullong, H5AC_dxpl_id);
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#endif /* FP_ULLONG */    
+#if LDOUBLE_ULLONG
     status |= H5T_register(H5T_PERS_HARD, "ldbl_ullong", native_ldouble, native_ullong, H5T_conv_ldouble_ullong, H5AC_dxpl_id);
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
-#endif /* H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM */
+#endif /* LDOUBLE_ULLONG */
 
     /*
      * The special no-op conversion is the fastest, so we list it last. The
diff --git a/src/H5Tconv.c b/src/H5Tconv.c
index cb1c38a..9da5842 100644
--- a/src/H5Tconv.c
+++ b/src/H5Tconv.c
@@ -190,6 +190,7 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
  * equal. In this case, do not return exception but make sure the maximum is assigned
  * to the destination.   SLU - 2005/06/29
  */
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_Xx_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     if (*((ST*)S) > (DT)(D_MAX)) {                                            \
         if(cb_struct.func) {			                              \
@@ -226,7 +227,13 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     } else 								      \
         *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_Xx_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_Ux_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     if (*((ST*)S) > (DT)(D_MAX)) {                                            \
         if(cb_struct.func) {			                              \
@@ -246,12 +253,18 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     } else								      \
         *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_Ux_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
 #define H5T_CONV_sS(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)<=sizeof(DT));					      \
     H5T_CONV(H5T_CONV_xX, long_long, STYPE, DTYPE, ST, DT, D_MIN, D_MAX)      \
 }
 
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_sU_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     if (*((ST*)S) < 0) {                                                      \
         if(cb_struct.func) {			                              \
@@ -271,23 +284,29 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     } else								      \
         *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_sU_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
 #define H5T_CONV_sU(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)<=sizeof(DT));					      \
     H5T_CONV(H5T_CONV_sU, long_long, STYPE, DTYPE, ST, DT, D_MIN, D_MAX)      \
 }
 
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_uS_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     if (sizeof(ST)==sizeof(DT) && *((ST*)S) > (D_MAX)) {                      \
         if(cb_struct.func) {                                                  \
-            H5T_conv_ret_t      except_ret;     /*callback return*/               \
-                                                                                  \
-            except_ret = (cb_struct.func)(H5T_CONV_EXCEPT_RANGE_HI,               \
-                    src_id, dst_id, S, D, cb_struct.user_data);                   \
-            if(except_ret == H5T_CONV_UNHANDLED)                                  \
-                /* Let compiler convert if case is ignored by user handler*/      \
+            H5T_conv_ret_t      except_ret;     /*callback return*/           \
+                                                                              \
+            except_ret = (cb_struct.func)(H5T_CONV_EXCEPT_RANGE_HI,           \
+                    src_id, dst_id, S, D, cb_struct.user_data);               \
+            if(except_ret == H5T_CONV_UNHANDLED)                              \
+                /* Let compiler convert if case is ignored by user handler*/  \
                 *((DT*)D) = (D_MAX);					      \
-            else if(except_ret == H5T_CONV_ABORT)                                 \
+            else if(except_ret == H5T_CONV_ABORT)                             \
                 HGOTO_ERROR(H5E_DATATYPE, H5E_CANTCONVERT, FAIL, "can't handle conversion exception") \
             /* if(except_ret==H5T_CONV_HANDLED): Fall through, user handled it */ \
         }                                                                     \
@@ -296,6 +315,11 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     } else								      \
         *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_uS_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
 #define H5T_CONV_uS(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)<=sizeof(DT));					      \
@@ -312,6 +336,7 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     H5T_CONV(H5T_CONV_Xx, long_long, STYPE, DTYPE, ST, DT, D_MIN, D_MAX)      \
 }
 
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_Su_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     if (*((ST*)S) < 0) {                                                      \
         if(cb_struct.func) {			                              \
@@ -346,6 +371,11 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     } else								      \
         *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_Su_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
 #define H5T_CONV_Su(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)>=sizeof(DT));					      \
@@ -362,6 +392,7 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     H5T_CONV(H5T_CONV_Ux, long_long, STYPE, DTYPE, ST, DT, D_MIN, D_MAX)      \
 }
 
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_su_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     /* Assumes memory format of unsigned & signed integers is same */	      \
     if (*((ST*)S) < 0) {                                                      \
@@ -379,14 +410,21 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
         }                                                                     \
         else                                                                  \
             *((DT*)D) = 0;					              \
-    }									      \
+    } else								      \
+        *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_su_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
 #define H5T_CONV_su(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)==sizeof(DT));					      \
     H5T_CONV(H5T_CONV_su, long_long, STYPE, DTYPE, ST, DT, D_MIN, D_MAX)      \
 }
 
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_us_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     /* Assumes memory format of unsigned & signed integers is same */	      \
     if (*((ST*)S) > (DT)(D_MAX)) {                                            \
@@ -404,8 +442,14 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
         }								      \
         else                                                                  \
             *((DT*)D) = (D_MAX);					      \
-    }									      \
+    } else								      \
+        *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#else
+#define H5T_CONV_us_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#endif
 
 #define H5T_CONV_us(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)==sizeof(DT));					      \
@@ -420,6 +464,7 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
 /* Same as H5T_CONV_Xx_CORE, except that instead of using D_MAX and D_MIN
  * when an overflow occurs, use the 'float' infinity values.
  */
+#ifdef H5_WANT_DCONV_EXCEPTION
 #define H5T_CONV_Ff_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
     if (*((ST*)S) > (DT)(D_MAX)) {                                            \
         if(cb_struct.func) {			                              \
@@ -454,6 +499,11 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     } else								      \
         *((DT*)D) = (DT)(*((ST*)S));					      \
 }
+#else
+#define H5T_CONV_Ff_CORE(S,D,STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {		      \
+    *((DT*)D) = (DT)(*((ST*)S));					      \
+}
+#endif
 
 #define H5T_CONV_Ff(STYPE,DTYPE,ST,DT,D_MIN,D_MAX) {			      \
     assert(sizeof(ST)>=sizeof(DT));					      \
@@ -7057,7 +7107,7 @@ done:
  *		destination values are packed.
  *-------------------------------------------------------------------------
  */
-#if H5_CONVERT_DENORMAL_FLOAT
+#if FP_FP
 herr_t
 H5T_conv_float_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7073,7 +7123,7 @@ H5T_conv_float_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_CONVERT_DENORMAL_FLOAT */
+#endif /* FP_FP */
 
 
 /*-------------------------------------------------------------------------
@@ -7091,7 +7141,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0
+#if FP_LDOUBLE
 herr_t
 H5T_conv_float_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7107,7 +7157,7 @@ H5T_conv_float_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0 */
+#endif /*FP_LDOUBLE*/
 
 
 /*-------------------------------------------------------------------------
@@ -7132,7 +7182,7 @@ done:
  *		destination values are packed.
  *-------------------------------------------------------------------------
  */
-#if H5_CONVERT_DENORMAL_FLOAT
+#if FP_FP
 herr_t
 H5T_conv_double_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7148,7 +7198,7 @@ H5T_conv_double_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /*H5_CONVERT_DENORMAL_FLOAT*/
+#endif /*FP_FP*/
 
 
 /*-------------------------------------------------------------------------
@@ -7166,7 +7216,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0
+#if FP_LDOUBLE
 herr_t
 H5T_conv_double_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7183,7 +7233,7 @@ H5T_conv_double_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0 */
+#endif /*FP_LDOUBLE*/
 
 
 /*-------------------------------------------------------------------------
@@ -7201,7 +7251,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0
+#if FP_LDOUBLE
 herr_t
 H5T_conv_ldouble_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7217,7 +7267,7 @@ H5T_conv_ldouble_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0 */
+#endif /* FP_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7235,7 +7285,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0
+#if FP_LDOUBLE
 herr_t
 H5T_conv_ldouble_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7251,7 +7301,7 @@ H5T_conv_ldouble_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_CONVERT_DENORMAL_FLOAT && H5_SIZEOF_LONG_DOUBLE !=0 */
+#endif /*FP_LDOUBLE*/
 
 
 /*-------------------------------------------------------------------------
@@ -7333,7 +7383,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_schar_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7349,7 +7399,7 @@ H5T_conv_schar_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7431,7 +7481,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_uchar_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7447,7 +7497,7 @@ H5T_conv_uchar_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7529,7 +7579,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_short_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7545,7 +7595,7 @@ H5T_conv_short_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7627,7 +7677,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_ushort_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7643,7 +7693,7 @@ H5T_conv_ushort_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7725,7 +7775,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_int_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7741,7 +7791,7 @@ H5T_conv_int_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7823,7 +7873,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_uint_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7839,7 +7889,7 @@ H5T_conv_uint_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7921,7 +7971,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_long_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7937,7 +7987,7 @@ H5T_conv_long_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -7955,7 +8005,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS
+#if ULONG_FP
 herr_t
 H5T_conv_ulong_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -7971,7 +8021,7 @@ H5T_conv_ulong_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS */
+#endif /* ULONG_FP */
 
 
 /*-------------------------------------------------------------------------
@@ -7989,7 +8039,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS
+#if ULONG_FP
 herr_t
 H5T_conv_ulong_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8005,7 +8055,7 @@ H5T_conv_ulong_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS */
+#endif /* ULONG_FP */
 
 
 /*-------------------------------------------------------------------------
@@ -8023,7 +8073,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS && H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if ULONG_LDOUBLE
 herr_t
 H5T_conv_ulong_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8039,7 +8089,7 @@ H5T_conv_ulong_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS && H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* ULONG_LDOUBLE */
 
 
 /*-------------------------------------------------------------------------
@@ -8121,7 +8171,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_INTEGER_TO_LDOUBLE_WORKS
+#if INTEGER_LDOUBLE
 herr_t
 H5T_conv_llong_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8137,9 +8187,8 @@ H5T_conv_llong_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_INTEGER_TO_LDOUBLE_WORKS */
+#endif /* INTEGER_LDOUBLE */
 
-#if H5_ULLONG_TO_FP_CAST_WORKS && H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS
 
 /*-------------------------------------------------------------------------
  * Function:	H5T_conv_ullong_float
@@ -8156,6 +8205,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
+#if ULLONG_FP
 herr_t
 H5T_conv_ullong_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8171,6 +8221,7 @@ H5T_conv_ullong_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
+#endif /*ULLONG_FP*/
 
 
 /*-------------------------------------------------------------------------
@@ -8188,6 +8239,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
+#if ULLONG_FP
 herr_t
 H5T_conv_ullong_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8203,6 +8255,7 @@ H5T_conv_ullong_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
+#endif /*ULLONG_FP*/
 
 
 /*-------------------------------------------------------------------------
@@ -8220,7 +8273,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_ULLONG_TO_LDOUBLE_PRECISION_WORKS
+#if ULLONG_LDOUBLE
 herr_t
 H5T_conv_ullong_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8236,8 +8289,7 @@ H5T_conv_ullong_ldouble (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_ULLONG_TO_LDOUBLE_PRECISION_WORKS */
-#endif /* H5_ULLONG_TO_FP_CAST_WORKS && H5_SW_ULONG_TO_FP_BOTTOM_BIT_WORKS */
+#endif /*ULLONG_LDOUBLE*/
 
 
 /*-------------------------------------------------------------------------
@@ -8383,7 +8435,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_schar (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8399,7 +8451,7 @@ H5T_conv_ldouble_schar (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
 
 /*-------------------------------------------------------------------------
@@ -8417,7 +8469,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_uchar (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8433,7 +8485,7 @@ H5T_conv_ldouble_uchar (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
 
 /*-------------------------------------------------------------------------
@@ -8579,7 +8631,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_short (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8595,7 +8647,7 @@ H5T_conv_ldouble_short (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
 
 /*-------------------------------------------------------------------------
@@ -8613,7 +8665,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_ushort (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8629,7 +8681,7 @@ H5T_conv_ldouble_ushort (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
 
 /*-------------------------------------------------------------------------
@@ -8775,7 +8827,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_int (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8791,7 +8843,7 @@ H5T_conv_ldouble_int (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
 
 /*-------------------------------------------------------------------------
@@ -8809,7 +8861,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS && H5_CV_LDOUBLE_TO_UINT_WORKS
+#if LDOUBLE_UINT
 herr_t
 H5T_conv_ldouble_uint (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8825,7 +8877,7 @@ H5T_conv_ldouble_uint (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS && H5_CV_LDOUBLE_TO_UINT_WORKS */
+#endif /* LDOUBLE_UINT */
 
 
 /*-------------------------------------------------------------------------
@@ -8971,7 +9023,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_long (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -8987,7 +9039,7 @@ H5T_conv_ldouble_long (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /*H5_SW_LDOUBLE_TO_INTEGER_WORKS*/
+#endif /*LDOUBLE_INTEGER*/
 
 
 /*-------------------------------------------------------------------------
@@ -9005,7 +9057,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_INTEGER
 herr_t
 H5T_conv_ldouble_ulong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9021,7 +9073,7 @@ H5T_conv_ldouble_ulong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /* LDOUBLE_INTEGER */
 
 
 /*-------------------------------------------------------------------------
@@ -9039,7 +9091,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#ifndef H5_HW_FP_TO_LLONG_NOT_WORKS
+#if FP_LLONG
 herr_t
 H5T_conv_float_llong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9055,7 +9107,7 @@ H5T_conv_float_llong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* !H5_HW_FP_TO_LLONG_NOT_WORKS */
+#endif /* FP_LLONG */
 
 
 /*-------------------------------------------------------------------------
@@ -9073,7 +9125,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM
+#if FP_ULLONG
 herr_t
 H5T_conv_float_ullong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9089,7 +9141,7 @@ H5T_conv_float_ullong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM */
+#endif /*FP_ULLONG*/
 
 
 /*-------------------------------------------------------------------------
@@ -9107,7 +9159,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#ifndef H5_HW_FP_TO_LLONG_NOT_WORKS
+#if FP_LLONG
 herr_t
 H5T_conv_double_llong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9123,7 +9175,7 @@ H5T_conv_double_llong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* !H5_HW_FP_TO_LLONG_NOT_WORKS */
+#endif /*FP_LLONG*/
 
 
 /*-------------------------------------------------------------------------
@@ -9141,7 +9193,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM
+#if FP_ULLONG
 herr_t
 H5T_conv_double_ullong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9157,7 +9209,7 @@ H5T_conv_double_ullong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM */
+#endif /*FP_ULLONG*/
 
 
 /*-------------------------------------------------------------------------
@@ -9175,7 +9227,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if !H5_HW_FP_TO_LLONG_NOT_WORKS && H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_LLONG
 herr_t
 H5T_conv_ldouble_llong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9191,7 +9243,7 @@ H5T_conv_ldouble_llong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* !H5_HW_FP_TO_LLONG_NOT_WORKS && H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /*LDOUBLE_LLONG*/ 
 
 
 /*-------------------------------------------------------------------------
@@ -9209,7 +9261,7 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-#if H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM && H5_SW_LDOUBLE_TO_INTEGER_WORKS
+#if LDOUBLE_ULLONG 
 herr_t
 H5T_conv_ldouble_ullong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 		       size_t nelmts, size_t buf_stride,
@@ -9225,7 +9277,7 @@ H5T_conv_ldouble_ullong (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 done:
     FUNC_LEAVE_NOAPI(ret_value);
 }
-#endif /* H5_FP_TO_ULLONG_BOTTOM_BIT_WORKS && H5_FP_TO_ULLONG_RIGHT_MAXIMUM && H5_SW_LDOUBLE_TO_INTEGER_WORKS */
+#endif /*LDOUBLE_ULLONG*/
 
 
 /*-------------------------------------------------------------------------
diff --git a/src/H5Tpkg.h b/src/H5Tpkg.h
index 6854bc2..1f406e8 100644
--- a/src/H5Tpkg.h
+++ b/src/H5Tpkg.h
@@ -64,6 +64,102 @@
 /* Macro to ease detecting atomic datatypes */
 #define H5T_IS_ATOMIC(dt)       (!(H5T_IS_COMPLEX((dt)->type) || (dt)->type==H5T_OPAQUE))
 
+
+/* Define an interim macro for converting between floating number(float and double) and floating number.
+ * All Cray compilers don't support denormalized floating values generating exception(?). */
+#if H5_CONVERT_DENORMAL_FLOAT
+#define FP_FP           1
+#endif /*H5_CONVERT_DENORMAL_FLOAT*/
+
+/* Define an interim macro for converting between floating number(float and double) and long double.
+ * All Cray compilers don't support denormalized floating values generating exception(?).  NEC doesn't
+ * support long double. */
+#if H5_SIZEOF_LONG_DOUBLE && H5_CONVERT_DENORMAL_FLOAT
+#define FP_LDOUBLE      1
+#endif /*H5_SIZEOF_LONG_DOUBLE && H5_CONVERT_DENORMAL_FLOAT*/
+
+/* Define an interim macro for converting all integers to long double.  SGI compilers give some 
+ * incorrect conversions. */
+#if (H5_WANT_DATA_ACCURACY && H5_INTEGER_TO_LDOUBLE_ACCURATE) || (!H5_WANT_DATA_ACCURACY)
+#define INTEGER_LDOUBLE         1
+#endif
+
+/* Define an interim macro for converting unsigned (long) long to floating numbers.
+ * 64-bit Solaris does different rounding. */ 
+#if (H5_WANT_DATA_ACCURACY && H5_ULONG_TO_FP_BOTTOM_BIT_ACCURATE) || (!H5_WANT_DATA_ACCURACY)
+#define ULONG_FP         1
+#endif
+
+/* Define an interim macro for converting unsigned long to long double.  SGI compilers give some
+ * incorrect conversions. 64-bit Solaris does different rounding. */
+#if (H5_WANT_DATA_ACCURACY && H5_INTEGER_TO_LDOUBLE_ACCURATE && H5_ULONG_TO_FP_BOTTOM_BIT_ACCURATE) || \
+    (!H5_WANT_DATA_ACCURACY)
+#define ULONG_LDOUBLE       1
+#endif
+
+/* Define an interim macro for converting unsigned long long to floating numbers.  SGI compilers give 
+ * some incorect conversion.  64-bit Solaris does different rounding.   Windows Visual Studio 6 does
+ * not support unsigned long long. */
+#if (H5_WANT_DATA_ACCURACY && H5_ULLONG_TO_FP_CAST_WORKS && H5_ULONG_TO_FP_BOTTOM_BIT_ACCURATE) || \
+    (!H5_WANT_DATA_ACCURACY && H5_ULLONG_TO_FP_CAST_WORKS)
+#define ULLONG_FP         1
+#endif
+
+/* Define an interim macro for converting unsigned long long to long double.  SGI compilers give 
+ * some incorect conversion.  64-bit Solaris does different rounding.   Windows Visual Studio 6 does
+ * not support unsigned long long.  For FreeBSD(sleipnir), the last 2 bytes of mantissa are lost when 
+ * compiler tries to do the conversion.  For Cygwin, compiler doesn't do rounding correctly. */
+#if (H5_WANT_DATA_ACCURACY && H5_ULLONG_TO_FP_CAST_WORKS && H5_ULONG_TO_FP_BOTTOM_BIT_ACCURATE && \
+    H5_ULLONG_TO_LDOUBLE_PRECISION) || (!H5_WANT_DATA_ACCURACY && H5_ULLONG_TO_FP_CAST_WORKS)
+#define ULLONG_LDOUBLE         1
+#endif
+
+/* Define an interim macro for converting long double to all integers.  SGI compilers give some incorrect
+ * conversions.  HP-UX 11.00 compiler generates floating exception. */
+#if (H5_WANT_DATA_ACCURACY && H5_LDOUBLE_TO_INTEGER_ACCURATE && H5_LDOUBLE_TO_INTEGER_WORKS) || \
+    (!H5_WANT_DATA_ACCURACY && H5_LDOUBLE_TO_INTEGER_WORKS)
+#define LDOUBLE_INTEGER         1
+#endif
+
+/* Define an interim macro for converting long double to unsigned int.  SGI compilers give some incorrect
+ * conversions.  HP-UX 11.00 compiler generates floating exception.  Some Intel compilers on some Linux
+ * give incorrect values. */
+#if (H5_WANT_DATA_ACCURACY && H5_LDOUBLE_TO_INTEGER_ACCURATE && H5_LDOUBLE_TO_UINT_ACCURATE && \
+    H5_LDOUBLE_TO_INTEGER_WORKS) || (!H5_WANT_DATA_ACCURACY && H5_LDOUBLE_TO_INTEGER_WORKS)
+#define LDOUBLE_UINT         1
+#endif
+
+/* Define an interim macro for converting floating numbers to long long.  The hard conversion on Windows 
+ * .NET 2003 has a bug and gives wrong exception value. */
+#if (H5_WANT_DATA_ACCURACY && !H5_HW_FP_TO_LLONG_NOT_WORKS) || (!H5_WANT_DATA_ACCURACY)
+#define FP_LLONG         1
+#endif
+
+/* Define an interim macro for converting long double to long long.  SGI compilers give some incorrect
+ * conversions.  HP-UX 11.00 compiler generates floating exception.  The hard conversion on Windows 
+ * .NET 2003 has a bug and gives wrong exception value. */
+#if (H5_WANT_DATA_ACCURACY && !H5_HW_FP_TO_LLONG_NOT_WORKS && H5_LDOUBLE_TO_INTEGER_ACCURATE && \
+    H5_LDOUBLE_TO_INTEGER_WORKS) || \
+    (!H5_WANT_DATA_ACCURACY && !H5_HW_FP_TO_LLONG_NOT_WORKS && H5_LDOUBLE_TO_INTEGER_WORKS)
+#define LDOUBLE_LLONG         1
+#endif
+
+/* Define an interim macro for converting floating numbers to unsigned long long.  PGI compiler does 
+ * roundup when the source fraction part is greater than 0.5.  HP-UX compilers set the maximal number 
+ * for unsigned long long as 0x7fffffffffffffff during conversion. */
+#if (H5_WANT_DATA_ACCURACY && H5_FP_TO_ULLONG_ACCURATE && H5_FP_TO_ULLONG_RIGHT_MAXIMUM) || \
+    (!H5_WANT_DATA_ACCURACY)
+#define FP_ULLONG         1
+#endif
+
+/* Define an interim macro for converting long double to all integers.  SGI compilers give some incorrect
+ * conversions.  HP-UX 11.00 compiler generates floating exception. */
+#if (H5_WANT_DATA_ACCURACY && H5_LDOUBLE_TO_INTEGER_ACCURATE && H5_LDOUBLE_TO_INTEGER_WORKS && \
+    H5_FP_TO_ULLONG_ACCURATE && H5_FP_TO_ULLONG_RIGHT_MAXIMUM) || \
+    (!H5_WANT_DATA_ACCURACY && H5_LDOUBLE_TO_INTEGER_WORKS)
+#define LDOUBLE_ULLONG         1
+#endif
+
 /* Statistics about a conversion function */
 struct H5T_stats_t {
     unsigned	ncalls;			/*num calls to conversion function   */
diff --git a/src/H5config.h.in b/src/H5config.h.in
index 0fb003c..e20fdbe 100644
--- a/src/H5config.h.in
+++ b/src/H5config.h.in
@@ -4,10 +4,6 @@
    values. */
 #undef CONVERT_DENORMAL_FLOAT
 
-/* Define if your system can convert long double to unsigned int values
-   correctly. */
-#undef CV_LDOUBLE_TO_UINT_WORKS
-
 /* Define if `dev_t' is a scalar */
 #undef DEV_T_IS_SCALAR
 
@@ -29,9 +25,9 @@
    integer values. */
 #undef FP_TO_INTEGER_OVERFLOW_WORKS
 
-/* Define if your system roundup accurately convert floating-point to unsigned
-   long long values. */
-#undef FP_TO_ULLONG_BOTTOM_BIT_WORKS
+/* Define if your system roundup accurately converting floating-point to
+   unsigned long long values. */
+#undef FP_TO_ULLONG_ACCURATE
 
 /* Define if your system has right maximum convert floating-point to unsigned
    long long values. */
@@ -361,6 +357,20 @@
 /* Define if `__tm_gmtoff' is a member of `struct tm' */
 #undef HAVE___TM_GMTOFF
 
+/* Define if your system can accurately convert from integers to long double
+   values. */
+#undef INTEGER_TO_LDOUBLE_ACCURATE
+
+/* Define if your system can convert long double to integers accurately. */
+#undef LDOUBLE_TO_INTEGER_ACCURATE
+
+/* Define if your system can convert from long double to integer values. */
+#undef LDOUBLE_TO_INTEGER_WORKS
+
+/* Define if your system can convert long double to unsigned int values
+   correctly. */
+#undef LDOUBLE_TO_UINT_ACCURATE
+
 /* Define if your system can compile long long to floating-point casts. */
 #undef LLONG_TO_FP_CAST_WORKS
 
@@ -507,18 +517,6 @@
 /* Define to 1 if you have the ANSI C header files. */
 #undef STDC_HEADERS
 
-/* Define if your system can accurately convert from integers to long double
-   values. */
-#undef SW_INTEGER_TO_LDOUBLE_WORKS
-
-/* Define if your system can accurately convert from long double to integer
-   values. */
-#undef SW_LDOUBLE_TO_INTEGER_WORKS
-
-/* Define if your system can accurately convert unsigned (long) long values to
-   floating-point values. */
-#undef SW_ULONG_TO_FP_BOTTOM_BIT_WORKS
-
 /* Define if your system supports pthread_attr_setscope(&attribute,
    PTHREAD_SCOPE_SYSTEM) call. */
 #undef SYSTEM_SCOPE_THREADS
@@ -535,7 +533,11 @@
 
 /* Define if your system can convert unsigned long long to long double with
    correct precision. */
-#undef ULLONG_TO_LDOUBLE_PRECISION_WORKS
+#undef ULLONG_TO_LDOUBLE_PRECISION
+
+/* Define if your system can accurately convert unsigned (long) long values to
+   floating-point values. */
+#undef ULONG_TO_FP_BOTTOM_BIT_ACCURATE
 
 /* Version number of package */
 #undef VERSION
@@ -544,6 +546,12 @@
    don't fit into size allowed */
 #undef VSNPRINTF_WORKS
 
+/* Data accuracy is prefered to speed during data conversions */
+#undef WANT_DATA_ACCURACY
+
+/* Check exception handling functions during data conversions */
+#undef WANT_DCONV_EXCEPTION
+
 /* Define if the HDF5 v1.6 compatibility functions are to be compiled in */
 #undef WANT_H5_V1_6_COMPAT