X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fceilf.m4;h=8b74a6d24e0d39577c0a9b9ff721f8bb8fe38dfa;hb=56005a21e8f9f434212a19dcb628c6d3b179fd08;hp=a33b9aa7e6ca6ca2da943db7fd1203d97f75cc0f;hpb=ec062d7a2671739dd977ebde3965fc93f8678a2e;p=gnulib.git

diff --git a/m4/ceilf.m4 b/m4/ceilf.m4
index a33b9aa7e..8b74a6d24 100644
--- a/m4/ceilf.m4
+++ b/m4/ceilf.m4
@@ -1,11 +1,12 @@
-# ceilf.m4 serial 7
-dnl Copyright (C) 2007, 2009-2010 Free Software Foundation, Inc.
+# ceilf.m4 serial 11
+dnl Copyright (C) 2007, 2009-2011 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.
 
 AC_DEFUN([gl_FUNC_CEILF],
 [
+  m4_divert_text([DEFAULTS], [gl_ceilf_required=plain])
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
   dnl Persuade glibc <math.h> to declare ceilf().
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
@@ -19,11 +20,51 @@ AC_DEFUN([gl_FUNC_CEILF],
       dnl libm.so, but not in the libm.so that the compiler uses.
       REPLACE_CEILF=1
     fi
+    m4_ifdef([gl_FUNC_CEILF_IEEE], [
+      if test $gl_ceilf_required = ieee && test $REPLACE_CEILF = 0; then
+        AC_CACHE_CHECK([whether ceilf works according to ISO C 99 with IEC 60559],
+          [gl_cv_func_ceilf_ieee],
+          [
+            save_LIBS="$LIBS"
+            LIBS="$LIBS $CEILF_LIBM"
+            AC_RUN_IFELSE(
+              [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+]gl_FLOAT_MINUS_ZERO_CODE[
+]gl_FLOAT_SIGNBIT_CODE[
+static float dummy (float f) { return 0; }
+int main (int argc, char *argv[])
+{
+  float (*my_ceilf) (float) = argc ? ceilf : dummy;
+  int result = 0;
+  /* Test whether ceilf (-0.0f) is -0.0f.  */
+  if (signbitf (minus_zerof) && !signbitf (my_ceilf (minus_zerof)))
+    result |= 1;
+  /* Test whether ceilf (-0.3f) is -0.0f.  */
+  if (signbitf (-0.3f) && !signbitf (my_ceilf (-0.3f)))
+    result |= 2;
+  return result;
+}
+              ]])],
+              [gl_cv_func_ceilf_ieee=yes],
+              [gl_cv_func_ceilf_ieee=no],
+              [gl_cv_func_ceilf_ieee="guessing no"])
+            LIBS="$save_LIBS"
+          ])
+        case "$gl_cv_func_ceilf_ieee" in
+          *yes) ;;
+          *) REPLACE_CEILF=1 ;;
+        esac
+      fi
+    ])
   else
     HAVE_DECL_CEILF=0
   fi
   if test $HAVE_DECL_CEILF = 0 || test $REPLACE_CEILF = 1; then
-    AC_LIBOBJ([ceilf])
+    dnl No libraries are needed to link lib/ceilf.c.
     CEILF_LIBM=
   fi
   AC_SUBST([CEILF_LIBM])