aclocal.m4 (AC_GCC_C_LONG_DOUBLE): New macro.

        * aclocal.m4 (AC_GCC_C_LONG_DOUBLE): New macro.

        * configure.in (AC_GCC_C_LONG_DOUBLE): Call it.

        * gansidecl.h (HAVE_LONG_DOUBLE): Define if gcc for stage2.

        * ggc-simple.c (HAVE_LONG_DOUBLE): Test before using long double.

From-SVN: r29432

gcc/ChangeLog

+Wed Sep 15 09:50:18 1999  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
+
+	* aclocal.m4 (AC_GCC_C_LONG_DOUBLE): New macro.
+
+	* configure.in (AC_GCC_C_LONG_DOUBLE): Call it.
+
+	* gansidecl.h (HAVE_LONG_DOUBLE): Define if gcc for stage2.
+
+	* ggc-simple.c (HAVE_LONG_DOUBLE): Test before using long double.
+
 Wed Sep 15 11:04:43 1999  Bernd Schmidt  <bernds@cygnus.co.uk>
 
 	* function.c (assign_parms): Delete arg SECOND_TIME.  Don't test it,

gcc/aclocal.m4

@@ -172,6 +172,25 @@ if test $gcc_cv_c_volatile = yes ; then
 fi
 ])
 
+dnl Check whether long double is supported.  This differs from the
+dnl built-in autoconf test in that it works for cross compiles.
+AC_DEFUN(AC_GCC_C_LONG_DOUBLE,
+[AC_CACHE_CHECK(for long double, gcc_cv_c_long_double,
+[if test "$GCC" = yes; then
+  gcc_cv_c_long_double=yes
+else
+AC_TRY_COMPILE(,
+[/* The Stardent Vistra knows sizeof(long double), but does not support it.  */
+long double foo = 0.0;
+/* On Ultrix 4.3 cc, long double is 4 and double is 8.  */
+switch (0) case 0: case (sizeof(long double) >= sizeof(double)):;],
+gcc_cv_c_long_double=yes, gcc_cv_c_long_double=no)
+fi])
+if test $gcc_cv_c_long_double = yes; then
+  AC_DEFINE(HAVE_LONG_DOUBLE)
+fi
+])
+
 dnl Define MKDIR_TAKES_ONE_ARG if mkdir accepts only one argument instead
 dnl of the usual 2.
 AC_DEFUN(GCC_FUNC_MKDIR_TAKES_ONE_ARG,

gcc/config.in

@@ -165,6 +165,9 @@
 /* Define if you don't have vprintf but do have _doprnt.  */
 #undef HAVE_DOPRNT
 
+/* Define if the `long double' type works.  */
+#undef HAVE_LONG_DOUBLE
+
 /* Define if you have a working `mmap' system call.  */
 #undef HAVE_MMAP
 

gcc/configure.in

@@ -284,6 +284,7 @@ AC_CANONICAL_SYSTEM
 
 # Find the native compiler
 AC_PROG_CC
+AC_GCC_C_LONG_DOUBLE
 
 # If the native compiler is GCC, we can enable warnings even in stage1.  
 # That's useful for people building cross-compilers, or just running a

gcc/gansidecl.h

@@ -45,6 +45,9 @@ Boston, MA 02111-1307, USA.  */
 # undef const
 # undef inline
 # define inline __inline__  /* Modern gcc can use `__inline__' freely. */
+# ifndef HAVE_LONG_DOUBLE
+#  define HAVE_LONG_DOUBLE 1
+# endif
 #endif /* GCC >= 2.7 */
 
 #ifndef NULL_PTR

gcc/ggc-simple.c

@@ -86,7 +86,11 @@ struct ggc_any
   union {
     char c;
     HOST_WIDE_INT i;
+#ifdef HAVE_LONG_DOUBLE
     long double d;
+#else
+    double d;
+#endif
   } u;
 };