X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=m4%2Fatanl.m4;h=46e08735cbf391e2b48b0ad045a296d76723c69d;hb=5191b3546cfb6c163228c23f214e325ddf60d46f;hp=28cf7b3a81f4112e5059800235f4d95cdae7d49c;hpb=b4349b948ba2c352187158e241334abda6e473e9;p=gnulib.git

diff --git a/m4/atanl.m4 b/m4/atanl.m4
index 28cf7b3a8..46e08735c 100644
--- a/m4/atanl.m4
+++ b/m4/atanl.m4
@@ -1,5 +1,5 @@
-# atanl.m4 serial 2
-dnl Copyright (C) 2010 Free Software Foundation, Inc.
+# atanl.m4 serial 8
+dnl Copyright (C) 2010-2013 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.
@@ -7,6 +7,8 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_ATANL],
 [
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+
   dnl Persuade glibc <math.h> to declare atanl().
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
 
@@ -14,12 +16,16 @@ AC_DEFUN([gl_FUNC_ATANL],
   AC_CACHE_CHECK([whether atanl() can be used without linking with libm],
     [gl_cv_func_atanl_no_libm],
     [
-      AC_TRY_LINK([#ifndef __NO_MATH_INLINES
-                   # define __NO_MATH_INLINES 1 /* for glibc */
-                   #endif
-                   #include <math.h>
-                   long double x;],
-                  [return atanl (x) > 1;],
+      AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[#ifndef __NO_MATH_INLINES
+             # define __NO_MATH_INLINES 1 /* for glibc */
+             #endif
+             #include <math.h>
+             long double (*funcptr) (long double) = atanl;
+             long double x;]],
+           [[return funcptr (x) > 1
+                    || atanl (x) > 1;]])],
         [gl_cv_func_atanl_no_libm=yes],
         [gl_cv_func_atanl_no_libm=no])
     ])
@@ -29,12 +35,16 @@ AC_DEFUN([gl_FUNC_ATANL],
       [
         save_LIBS="$LIBS"
         LIBS="$LIBS -lm"
-        AC_TRY_LINK([#ifndef __NO_MATH_INLINES
-                     # define __NO_MATH_INLINES 1 /* for glibc */
-                     #endif
-                     #include <math.h>
-                     long double x;],
-                    [return atanl (x) > 1;],
+        AC_LINK_IFELSE(
+          [AC_LANG_PROGRAM(
+             [[#ifndef __NO_MATH_INLINES
+               # define __NO_MATH_INLINES 1 /* for glibc */
+               #endif
+               #include <math.h>
+               long double (*funcptr) (long double) = atanl;
+               long double x;]],
+             [[return funcptr (x) > 1
+                      || atanl (x) > 1;]])],
           [gl_cv_func_atanl_in_libm=yes],
           [gl_cv_func_atanl_in_libm=no])
         LIBS="$save_LIBS"
@@ -46,18 +56,23 @@ AC_DEFUN([gl_FUNC_ATANL],
   if test $gl_cv_func_atanl_no_libm = yes \
      || test $gl_cv_func_atanl_in_libm = yes; then
     dnl Also check whether it's declared.
-    dnl MacOS X 10.3 has atanl() in libc but doesn't declare it in <math.h>.
-    AC_CHECK_DECL([atanl], , [HAVE_DECL_ATANL=0], [#include <math.h>])
+    dnl Mac OS X 10.3 has atanl() in libc but doesn't declare it in <math.h>.
+    AC_CHECK_DECL([atanl], , [HAVE_DECL_ATANL=0], [[#include <math.h>]])
   else
     HAVE_DECL_ATANL=0
     HAVE_ATANL=0
-    AC_LIBOBJ([atanl])
-    AC_REQUIRE([gl_FUNC_ISNANL])
-    dnl Append $ISNANL_LIBM to ATANL_LIBM, avoiding gratuitous duplicates.
-    case " $ATANL_LIBM " in
-      *" $ISNANL_LIBM "*) ;;
-      *) ATANL_LIBM="$ATANL_LIBM $ISNANL_LIBM" ;;
-    esac
+    dnl Find libraries needed to link lib/atanl.c.
+    if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+      AC_REQUIRE([gl_FUNC_ATAN])
+      ATANL_LIBM="$ATAN_LIBM"
+    else
+      AC_REQUIRE([gl_FUNC_ISNANL])
+      dnl Append $ISNANL_LIBM to ATANL_LIBM, avoiding gratuitous duplicates.
+      case " $ATANL_LIBM " in
+        *" $ISNANL_LIBM "*) ;;
+        *) ATANL_LIBM="$ATANL_LIBM $ISNANL_LIBM" ;;
+      esac
+    fi
   fi
   AC_SUBST([ATANL_LIBM])
 ])