Fix formula.

[gnulib.git] / m4 / printf-frexpl.m4

diff --git a/m4/printf-frexpl.m4 b/m4/printf-frexpl.m4
index e21ae36..d522d0e 100644 (file)
--- a/m4/printf-frexpl.m4
+++ b/m4/printf-frexpl.m4
@@ -1,4 +1,4 @@
-# printf-frexpl.m4 serial 2
+# printf-frexpl.m4 serial 3
 dnl Copyright (C) 2007 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -9,6 +9,7 @@ dnl Check how to define printf_frexpl() without linking with libm.
 AC_DEFUN([gl_FUNC_PRINTF_FREXPL],
 [
   AC_REQUIRE([gt_TYPE_LONGDOUBLE])
+  AC_REQUIRE([gl_MATH_H_DEFAULTS])
   if test $gt_cv_c_long_double = yes; then
     AC_CACHE_CHECK([whether frexpl can be used without linking with libm],
       [gl_cv_func_frexpl_no_libm],
@@ -23,9 +24,9 @@ AC_DEFUN([gl_FUNC_PRINTF_FREXPL],
     if test $gl_cv_func_frexpl_no_libm = yes; then
       AC_DEFINE([HAVE_FREXPL_IN_LIBC], 1,
         [Define if the frexpl function is available in libc.])
-      dnl Also check whether it's declared. glibc (2.3..2.5 at least) and
-      dnl MacOS X 10.3 have frexpl() in libc but don't declare it in <math.h>.
-      AC_CHECK_DECLS([frexpl])
+      dnl Also check whether it's declared.
+      dnl MacOS X 10.3 has frexpl() in libc but doesn't declare it in <math.h>.
+      AC_CHECK_DECL([frexpl], , [HAVE_DECL_FREXPL=0], [#include <math.h>])
     fi
 
     AC_CACHE_CHECK([whether ldexpl can be used without linking with libm],
@@ -41,9 +42,9 @@ AC_DEFUN([gl_FUNC_PRINTF_FREXPL],
     if test $gl_cv_func_ldexpl_no_libm = yes; then
       AC_DEFINE([HAVE_LDEXPL_IN_LIBC], 1,
         [Define if the ldexpl function is available in libc.])
-      dnl Also check whether it's declared. glibc (2.3..2.5 at least) and
-      dnl MacOS X 10.3 have ldexpl() in libc but don't declare it in <math.h>.
-      AC_CHECK_DECLS([ldexpl])
+      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>])
     fi
   fi
 ])