[svn-r27439] Merged r27428 from trunk.

Bug fix: DAILYTEST-170
Description:
    XL compilers in ostrich (PowerPC64 linux) fail in test/dt_arith
    because of the removal of the LLONG_TO_LDOUBLE_CORRECT (removed in
    r26625) and LDOUBLE_TO_LLONG_ACCURATE (removed in r26623).

Solution:
    Reverse revisions
	r26623: bring back LDOUBLE_TO_LLONG_ACCURATE configure macro
	r26625: bring back LLONG_TO_LDOUBLE_CORRECT configure macro
	r26627: bring back WANT_DATA_ACCURACY configure macro which is
	    used together with the above two macros. This also brings
	    back the enable-dconv-accuracy configure option.

Tested: platypus & kituo, using --enable-fortran, --enable-cxx. Also in Ostrich using
both GCC and XL compilers.

1 files changed, 214 insertions, 0 deletions

diff --git a/configure b/configure
index 75c32a6..9da64f6 100755
--- a/configure
+++ b/configure
@@ -911,6 +911,7 @@ with_mpe
 enable_direct_vfd
 with_default_plugindir
 enable_dconv_exception
+enable_dconv_accuracy
 enable_build_all
 enable_deprecated_symbols
 with_default_api_version
@@ -1608,6 +1609,8 @@ Optional Features:
   --enable-dconv-exception
                           if exception handling functions is checked during
                           data conversions [default=yes]
+  --enable-dconv-accuracy if data accuracy is guaranteed during data
+                          conversions [default=yes]
   --enable-build-all      Build helper programs that only developers should
                           need [default=no]
   --enable-deprecated-symbols
@@ -27465,6 +27468,33 @@ $as_echo "no" >&6; }
 fi
 
 ## ----------------------------------------------------------------------
+## Decide whether the data accuracy has higher priority during data
+## conversions.  If not, some hard conversions will still be prefered even
+## though the data may be wrong (for example, some compilers don't
+## support denormalized floating values) to maximize speed.
+##
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether data accuracy is guaranteed during data conversions" >&5
+$as_echo_n "checking whether data accuracy is guaranteed during data conversions... " >&6; }
+# Check whether --enable-dconv-accuracy was given.
+if test "${enable_dconv_accuracy+set}" = set; then :
+  enableval=$enable_dconv_accuracy; DATA_ACCURACY=$enableval
+else
+  DATA_ACCURACY=yes
+fi
+
+
+if test "$DATA_ACCURACY" = "yes"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+
+$as_echo "#define WANT_DATA_ACCURACY 1" >>confdefs.h
+
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+## ----------------------------------------------------------------------
 ## Set the flag to indicate that the machine has window style pathname,
 ## that is, "drive-letter:\" (e.g. "C:") or "drive-letter:/" (e.g. "C:/").
 ## (This flag should be _unset_ for all machines, except for Windows, where
@@ -27728,6 +27758,190 @@ $as_echo "no" >&6; }
 fi
 
 ## ----------------------------------------------------------------------
+## Set the flag to indicate that the machine can accurately convert
+## 'long double' to '(unsigned) long long' values.  (This flag should
+## be set for all machines, except for Mac OS 10.4, SGI IRIX64 6.5 and
+## Powerpc Linux using XL compilers.
+## When the bit sequence of long double is 0x4351ccf385ebc8a0bfcc2a3c...,
+## the values of (unsigned)long long start to go wrong on these
+## two machines.  Adjusting it higher to 0x4351ccf385ebc8a0dfcc... or
+## 0x4351ccf385ebc8a0ffcc... will make the converted values wildly wrong.
+## This test detects this wrong behavior and disable the test.
+##
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if correctly converting long double to (unsigned) long long values" >&5
+$as_echo_n "checking if correctly converting long double to (unsigned) long long values... " >&6; }
+
+if test ${ac_cv_sizeof_long_double} = 0; then
+   hdf5_cv_ldouble_to_llong_accurate=${hdf5_cv_ldouble_to_llong_accurate=no}
+else
+   if ${hdf5_cv_ldouble_to_llong_accurate+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test "$cross_compiling" = yes; then :
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error $? "cannot run test program while cross compiling
+See \`config.log' for more details" "$LINENO" 5; }
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+        int main(void)
+        {
+            long double         ld = 20041683600089727.779961L;
+            long long           ll;
+            unsigned long long  ull;
+            unsigned char       s[16];
+            int                 ret = 0;
+
+            if(sizeof(long double) == 16) {
+                /*make sure the long double type is the same as the failing type
+                 *which has 16 bytes in size and 11 bits of exponent.  If it is,
+                 *the bit sequence should be like below.  It's not
+                 *a decent way to check but this info isn't available. */
+                memcpy(s, &ld, 16);
+                if(s[0]==0x43 && s[1]==0x51 && s[2]==0xcc && s[3]==0xf3 &&
+                    s[4]==0x85 && s[5]==0xeb && s[6]==0xc8 && s[7]==0xa0 &&
+                    s[8]==0xbf && s[9]==0xcc && s[10]==0x2a && s[11]==0x3c) {
+
+                    /*slightly adjust the bit sequence (s[8]=0xdf).  The converted
+                     *values will go wild on Mac OS 10.4 and IRIX64 6.5.*/
+                    s[0]=0x43; s[1]=0x51; s[2]=0xcc; s[3]=0xf3;
+                    s[4]=0x85; s[5]=0xeb; s[6]=0xc8; s[7]=0xa0;
+                    s[8]=0xdf; s[9]=0xcc; s[10]=0x2a; s[11]=0x3c;
+                    s[12]=0x3d; s[13]=0x85; s[14]=0x56; s[15]=0x20;
+
+                    memcpy(&ld, s, 16);
+                    ll = (long long)ld;
+                    ull = (unsigned long long)ld;
+
+                    if(ll != 20041683600089728 || ull != 20041683600089728)
+                        ret = 1;
+                }
+            }
+    done:
+            exit(ret);
+        }
+
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+  hdf5_cv_ldouble_to_llong_accurate=yes
+else
+  hdf5_cv_ldouble_to_llong_accurate=no
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+fi
+
+fi
+
+if test ${hdf5_cv_ldouble_to_llong_accurate} = "yes"; then
+
+$as_echo "#define LDOUBLE_TO_LLONG_ACCURATE 1" >>confdefs.h
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+## ----------------------------------------------------------------------
+## Set the flag to indicate that the machine can accurately convert
+## '(unsigned) long long' to 'long double' values.  (This flag should be
+## set for all machines, except for Mac OS 10.4 and Powerpc Linux using
+## XL compilers.
+## When the bit sequences are 003fff..., 007fff..., 00ffff..., 01ffff...,
+## ..., 7fffff..., the converted values are twice as big as they should be.
+##
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if correctly converting (unsigned) long long to long double values" >&5
+$as_echo_n "checking if correctly converting (unsigned) long long to long double values... " >&6; }
+
+if test ${ac_cv_sizeof_long_double} = 0; then
+   hdf5_cv_llong_to_ldouble_correct=${hdf5_cv_llong_to_ldouble_correct=no}
+else
+   if ${hdf5_cv_llong_to_ldouble_correct+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test "$cross_compiling" = yes; then :
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error $? "cannot run test program while cross compiling
+See \`config.log' for more details" "$LINENO" 5; }
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+        int main(void)
+        {
+            long double         ld;
+            long long           ll;
+            unsigned long long  ull;
+            unsigned char       s[16];
+            int                 flag=0, ret=0;
+
+            /*Determine if long double has 16 byte in size, 11 bit exponent, and
+             *the bias is 0x3ff */
+            if(sizeof(long double) == 16) {
+                ld = 1.0L;
+                memcpy(s, &ld, 16);
+                if(s[0]==0x3f && s[1]==0xf0 && s[2]==0x00 && s[3]==0x00 &&
+                    s[4]==0x00 && s[5]==0x00 && s[6]==0x00 && s[7]==0x00)
+                    flag = 1;
+            }
+
+            if(flag==1 && sizeof(long long)==8) {
+                ll = 0x01ffffffffffffffLL;
+                ld = (long double)ll;
+                memcpy(s, &ld, 16);
+                /*Check if the bit sequence is as supposed to be*/
+                if(s[0]!=0x43 || s[1]!=0x7f || s[2]!=0xff || s[3]!=0xff ||
+                    s[4]!=0xff || s[5]!=0xff || s[6]!=0xff || s[7]!=0xff ||
+                    s[8]!=0xf0 || s[9]!=0x00 || s[10]!=0x00 || s[11]!=0x00)
+                    ret = 1;
+            }
+            if(flag==1 && sizeof(unsigned long long)==8) {
+                ull = 0x01ffffffffffffffULL;
+                ld = (long double)ull;
+                memcpy(s, &ld, 16);
+                if(s[0]!=0x43 || s[1]!=0x7f || s[2]!=0xff || s[3]!=0xff ||
+                    s[4]!=0xff || s[5]!=0xff || s[6]!=0xff || s[7]!=0xff ||
+                    s[8]!=0xf0 || s[9]!=0x00 || s[10]!=0x00 || s[11]!=0x00)
+                    ret = 1;
+            }
+    done:
+            exit(ret);
+        }
+
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+  hdf5_cv_llong_to_ldouble_correct=yes
+else
+  hdf5_cv_llong_to_ldouble_correct=no
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+fi
+
+fi
+
+if test ${hdf5_cv_llong_to_ldouble_correct} = "yes"; then
+
+$as_echo "#define LLONG_TO_LDOUBLE_CORRECT 1" >>confdefs.h
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+## ----------------------------------------------------------------------
 ## Set some variables for general configuration information to be saved
 ## and installed with the libraries (used to generate libhdf5.settings).
 ##