X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fldexpl.m4;h=84f09771859663a5e3507dcc8c29032f37fd6a68;hb=4d319c3618a4668216195af1400afa8fb0549d6e;hp=804f1b8ad7564e3d822b0c2ba626f05928b33c3d;hpb=aecb65d22ea2a79b4f171eeac3031b6db43a49fb;p=gnulib.git

diff --git a/m4/ldexpl.m4 b/m4/ldexpl.m4
index 804f1b8ad..84f097718 100644
--- a/m4/ldexpl.m4
+++ b/m4/ldexpl.m4
@@ -1,5 +1,5 @@
-# ldexpl.m4 serial 2
-dnl Copyright (C) 2007 Free Software Foundation, Inc.
+# ldexpl.m4 serial 7
+dnl Copyright (C) 2007-2010 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -7,7 +7,57 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_LDEXPL],
 [
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  dnl Check whether it's declared.
+  dnl MacOS X 10.3 has ldexpl() in libc but doesn't declare it in <math.h>.
+  AC_CHECK_DECL([ldexpl], , [HAVE_DECL_LDEXPL=0], [#include <math.h>])
   LDEXPL_LIBM=
+  if test $HAVE_DECL_LDEXPL = 1; then
+    gl_CHECK_LDEXPL_NO_LIBM
+    if test $gl_cv_func_ldexpl_no_libm = no; then
+      AC_CACHE_CHECK([whether ldexpl() can be used with libm],
+        [gl_cv_func_ldexpl_in_libm],
+        [
+          save_LIBS="$LIBS"
+          LIBS="$LIBS -lm"
+          AC_TRY_LINK([#include <math.h>
+                       long double x;],
+                      [return ldexpl (x, -1) > 0;],
+            [gl_cv_func_ldexpl_in_libm=yes],
+            [gl_cv_func_ldexpl_in_libm=no])
+          LIBS="$save_LIBS"
+        ])
+      if test $gl_cv_func_ldexpl_in_libm = yes; then
+        LDEXPL_LIBM=-lm
+      fi
+    fi
+    if test $gl_cv_func_ldexpl_no_libm = yes \
+       || test $gl_cv_func_ldexpl_in_libm = yes; then
+      save_LIBS="$LIBS"
+      LIBS="$LIBS $LDEXPL_LIBM"
+      gl_FUNC_LDEXPL_WORKS
+      LIBS="$save_LIBS"
+      case "$gl_cv_func_ldexpl_works" in
+        *yes) gl_func_ldexpl=yes ;;
+        *)    gl_func_ldexpl=no; REPLACE_LDEXPL=1; LDEXPL_LIBM= ;;
+      esac
+    else
+      gl_func_ldexpl=no
+    fi
+    if test $gl_func_ldexpl = yes; then
+      AC_DEFINE([HAVE_LDEXPL], [1],
+        [Define if the ldexpl() function is available.])
+    fi
+  fi
+  if test $HAVE_DECL_LDEXPL = 0 || test $gl_func_ldexpl = no; then
+    AC_LIBOBJ([ldexpl])
+  fi
+  AC_SUBST([LDEXPL_LIBM])
+])
+
+dnl Test whether ldexpl() can be used without linking with libm.
+dnl Set gl_cv_func_ldexpl_no_libm to 'yes' or 'no' accordingly.
+AC_DEFUN([gl_CHECK_LDEXPL_NO_LIBM],
+[
   AC_CACHE_CHECK([whether ldexpl() can be used without linking with libm],
     [gl_cv_func_ldexpl_no_libm],
     [
@@ -17,50 +67,10 @@ AC_DEFUN([gl_FUNC_LDEXPL],
         [gl_cv_func_ldexpl_no_libm=yes],
         [gl_cv_func_ldexpl_no_libm=no])
     ])
-  if test $gl_cv_func_ldexpl_no_libm = no; then
-    AC_CACHE_CHECK([whether ldexpl() can be used with libm],
-      [gl_cv_func_ldexpl_in_libm],
-      [
-        save_LIBS="$LIBS"
-        LIBS="$LIBS -lm"
-        AC_TRY_LINK([#include <math.h>
-                     long double x;],
-                    [return ldexpl (x, -1) > 0;],
-          [gl_cv_func_ldexpl_in_libm=yes],
-          [gl_cv_func_ldexpl_in_libm=no])
-        LIBS="$save_LIBS"
-      ])
-    if test $gl_cv_func_ldexpl_in_libm = yes; then
-      LDEXPL_LIBM=-lm
-    fi
-  fi
-  if test $gl_cv_func_ldexpl_no_libm = yes \
-     || test $gl_cv_func_ldexpl_in_libm = yes; then
-    save_LIBS="$LIBS"
-    LIBS="$LIBS $LDEXPL_LIBM"
-    gl_FUNC_LDEXPL_WORKS
-    LIBS="$save_LIBS"
-    case "$gl_cv_func_ldexpl_works" in
-      *yes) gl_func_ldexpl=yes ;;
-      *)    gl_func_ldexpl=no; REPLACE_LDEXPL=1; LDEXPL_LIBM= ;;
-    esac
-  else
-    gl_func_ldexpl=no
-  fi
-  if test $gl_func_ldexpl = yes; then
-    AC_DEFINE([HAVE_LDEXPL], 1,
-      [Define if the ldexpl() function is available.])
-    dnl Also check whether it's declared.
-    dnl MacOS X 10.3 has ldexpl() in libc but doesn't declare it in <math.h>.
-    AC_CHECK_DECL([ldexpl], , [HAVE_DECL_LDEXPL=0], [#include <math.h>])
-  else
-    HAVE_DECL_LDEXPL=0
-    AC_LIBOBJ([ldexpl])
-  fi
-  AC_SUBST([LDEXPL_LIBM])
 ])
 
-dnl Test whether ldexpl() works on finite numbers (this fails on AIX 5.1).
+dnl Test whether ldexpl() works on finite numbers (this fails on AIX 5.1
+dnl and MacOS X 10.4/PowerPC).
 AC_DEFUN([gl_FUNC_LDEXPL_WORKS],
 [
   AC_REQUIRE([AC_PROG_CC])
@@ -72,14 +82,19 @@ AC_DEFUN([gl_FUNC_LDEXPL_WORKS],
 extern long double ldexpl (long double, int);
 int main()
 {
-  volatile long double x = 1.0;
-  volatile long double y = ldexpl (x, -1);
-  return (y != 0.5L);
+  volatile long double x1 = 1.0;
+  volatile long double y1 = ldexpl (x1, -1);
+  volatile long double x2 = 1.73205L;
+  volatile long double y2 = ldexpl (x2, 0);
+  return (y1 != 0.5L) || (y2 != x2);
 }], [gl_cv_func_ldexpl_works=yes], [gl_cv_func_ldexpl_works=no],
-      [case "$host_os" in
-         aix*) gl_cv_func_ldexpl_works="guessing no";;
-         *)    gl_cv_func_ldexpl_works="guessing yes";;
+      [
+changequote(,)dnl
+       case "$host_os" in
+         aix | aix[3-6]*) gl_cv_func_ldexpl_works="guessing no";;
+         *)               gl_cv_func_ldexpl_works="guessing yes";;
        esac
+changequote([,])dnl
       ])
     ])
 ])