reverted commit 10144 (wrongly applied to branch 3.1 instead of trunk)

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/branches/3.1@10149 280ebfd0-de03-0410-8827-d642c229c3f4

2 files changed, 11 insertions, 103 deletions

diff --git a/configure.ac b/configure.ac
index 10368870f..7b944d92a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -252,40 +252,6 @@ AC_LANG(C)
 dnl Support unusual archivers.
 AM_PROG_AR
 
-dnl Try to determine the double format
-AC_MSG_CHECKING(format of `double')
-AC_RUN_IFELSE([AC_LANG_PROGRAM([[
-#include <stdint.h>
-]], [[
-union ieee_double_extract
-{
-  double d;
-  uint32_t x[2];
-} t;
-t.d = 1.000000476837158203125; /* 1 + 1/2^21, which has manl = 2^31,
-    manh = 0, exp = 1023 and sig = 0 */
-if (t.x[0] == 2147483648UL && t.x[1] == 1072693248UL)
-   return 1; /* little endian */
-else if (t.x[0] == 1072693248UL && t.x[1] == 2147483648UL)
-   return 2; /* little endian swapped */
-else if (t.x[0] == 1024 && t.x[1] == 2147483648UL)
-   return 3; /* big endian */
-else
-   return 0; /* unknown */
-]])],
-   [mpfr_ieee_double=$?],
-   [mpfr_ieee_double=$?],
-   [mpfr_ieee_double=0])
-case "$mpfr_ieee_double" in
-  1) AC_MSG_RESULT(little endian)
-     AC_DEFINE(HAVE_DOUBLE_IEEE_LITTLE_ENDIAN) ;;
-  2) AC_MSG_RESULT(little endian swapped)
-     AC_DEFINE(HAVE_DOUBLE_IEEE_LITTLE_SWAPPED) ;;
-  3) AC_MSG_RESULT(big endian)
-     AC_DEFINE(HAVE_DOUBLE_IEEE_BIG_ENDIAN) ;;
-  *) AC_MSG_ERROR(format of 'double' not recognized) ;;
-esac
-
 dnl For GCC, _Decimal64 was introduced in GCC 4.3 for some targets
 dnl (note that it is not guaranteed to be available because it may
 dnl be disabled in the GCC build). See:
@@ -304,12 +270,17 @@ AC_ARG_ENABLE(decimal-float,
            AC_MSG_CHECKING(if compiler knows _Decimal64)
            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[_Decimal64 x;]])],
               [AC_MSG_RESULT(yes)
-               AC_MSG_CHECKING(if 'double' format is known)
-               case $mpfr_ieee_double in
-               0) AC_MSG_RESULT(no)
-                  AC_MSG_ERROR([unknown 'double' format]) ;;
-               *) AC_MSG_RESULT(yes)
-               esac
+               if test "$use_gmp_build" != yes ; then
+                  AC_MSG_ERROR([decimal float support requires --with-gmp-build])
+               fi
+               AC_MSG_CHECKING(if _GMP_IEEE_FLOATS is defined)
+               AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+#include "gmp.h"
+#include "gmp-impl.h"
+#ifndef _GMP_IEEE_FLOATS
+#error "_GMP_IEEE_FLOATS is not defined"
+#endif]])],[AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)
+                  AC_MSG_ERROR([decimal float support requires _GMP_IEEE_FLOATS])])
               ],
               [AC_MSG_RESULT(no)
 AC_MSG_ERROR([Compiler doesn't know _Decimal64 (ISO/IEC TR 24732).
diff --git a/src/mpfr-gmp.h b/src/mpfr-gmp.h
index 267375ebb..445b35338 100644
--- a/src/mpfr-gmp.h
+++ b/src/mpfr-gmp.h
@@ -405,69 +405,6 @@ typedef struct {mp_limb_t inv32;} mpfr_pi1_t; /* We changed gmp_pi1_t into
       }                                                                 \
   } while (0)
 
-/* ieee_double_extract structure (copied from GMP 6.1.0, gmp-impl.h) */
-
-/* Define ieee_double_extract and _GMP_IEEE_FLOATS.
-
-   Bit field packing is "implementation defined" according to C99, which
-   leaves us at the compiler's mercy here.  For some systems packing is
-   defined in the ABI (eg. x86).  In any case so far it seems universal that
-   little endian systems pack from low to high, and big endian from high to
-   low within the given type.
-
-   Within the fields we rely on the integer endianness being the same as the
-   float endianness, this is true everywhere we know of and it'd be a fairly
-   strange system that did anything else.  */
-
-#ifndef _GMP_IEEE_FLOATS
-
-#if HAVE_DOUBLE_IEEE_LITTLE_SWAPPED
-#define _GMP_IEEE_FLOATS 1
-union ieee_double_extract
-{
-  struct
-    {
-      unsigned long manh:20;
-      unsigned long exp:11;
-      unsigned long sig:1;
-      unsigned long manl:32;
-    } s;
-  double d;
-};
-#endif
-
-#if HAVE_DOUBLE_IEEE_LITTLE_ENDIAN
-#define _GMP_IEEE_FLOATS 1
-union ieee_double_extract
-{
-  struct
-    {
-      unsigned long manl:32;
-      unsigned long manh:20;
-      unsigned long exp:11;
-      unsigned long sig:1;
-    } s;
-  double d;
-};
-#endif
-
-#if HAVE_DOUBLE_IEEE_BIG_ENDIAN
-#define _GMP_IEEE_FLOATS 1
-union ieee_double_extract
-{
-  struct
-    {
-      unsigned long sig:1;
-      unsigned long exp:11;
-      unsigned long manh:20;
-      unsigned long manl:32;
-    } s;
-  double d;
-};
-#endif
-
-#endif /* _GMP_IEEE_FLOATS */
-
 #if defined (__cplusplus)
 }
 #endif