[svn-r27428] 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:
    h5committested.
    Also tested in ostrich using the XL compilers.

1 files changed, 82 insertions, 0 deletions

diff --git a/config/cmake/ConversionTests.c b/config/cmake/ConversionTests.c
index cd2e8bb..d964bf8 100644
--- a/config/cmake/ConversionTests.c
+++ b/config/cmake/ConversionTests.c
@@ -116,6 +116,88 @@ done:
 
 #endif
 
+#ifdef H5_LDOUBLE_TO_LLONG_ACCURATE_TEST
+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);
+}
+#endif
+
+#ifdef H5_LLONG_TO_LDOUBLE_CORRECT_TEST
+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);
+}
+#endif
+
 #ifdef H5_NO_ALIGNMENT_RESTRICTIONS_TEST
 
 #include <stdlib.h>