X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Froundl.m4;h=90c6bd0165ce0090fc12601870e2e5b983443aa3;hb=cd56634a4a8179fd5a4419fbb3e27211b042ab1c;hp=1d2558510c306d917cff4d581aafaa7066856409;hpb=d599e5add275f75ed08e6527b8ee4d3f4f7c3aea;p=gnulib.git

diff --git a/m4/roundl.m4 b/m4/roundl.m4
index 1d2558510..90c6bd016 100644
--- a/m4/roundl.m4
+++ b/m4/roundl.m4
@@ -1,5 +1,5 @@
-# roundl.m4 serial 8
-dnl Copyright (C) 2007, 2009-2011 Free Software Foundation, Inc.
+# roundl.m4 serial 15
+dnl Copyright (C) 2007, 2009-2014 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.
@@ -8,16 +8,27 @@ AC_DEFUN([gl_FUNC_ROUNDL],
 [
   m4_divert_text([DEFAULTS], [gl_roundl_required=plain])
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
+
   dnl Persuade glibc <math.h> to declare roundl().
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
-  AC_CHECK_DECLS([roundl], , , [#include <math.h>])
-  if test "$ac_cv_have_decl_roundl" = yes; then
-    gl_CHECK_MATH_LIB([ROUNDL_LIBM], [x = roundl (x);])
-    if test "$ROUNDL_LIBM" = missing; then
-      REPLACE_ROUNDL=1
-    fi
+
+  gl_CHECK_MATH_LIB([ROUNDL_LIBM], [x = roundl (x);],
+    [extern
+     #ifdef __cplusplus
+     "C"
+     #endif
+     long double roundl (long double);
+    ])
+  if test "$ROUNDL_LIBM" != missing; then
+    HAVE_ROUNDL=1
+    dnl Also check whether it's declared.
+    dnl IRIX 6.5 has roundl() in libm but doesn't declare it in <math.h>.
+    AC_CHECK_DECLS([roundl], , [HAVE_DECL_ROUNDL=0], [[#include <math.h>]])
+
     m4_ifdef([gl_FUNC_ROUNDL_IEEE], [
       if test $gl_roundl_required = ieee && test $REPLACE_ROUNDL = 0; then
+        AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
         AC_CACHE_CHECK([whether roundl works according to ISO C 99 with IEC 60559],
           [gl_cv_func_roundl_ieee],
           [
@@ -29,19 +40,36 @@ AC_DEFUN([gl_FUNC_ROUNDL],
 # define __NO_MATH_INLINES 1 /* for glibc */
 #endif
 #include <math.h>
+extern
+#ifdef __cplusplus
+"C"
+#endif
+long double roundl (long double);
 ]gl_LONG_DOUBLE_MINUS_ZERO_CODE[
 ]gl_LONG_DOUBLE_SIGNBIT_CODE[
-int main()
+static long double dummy (long double f) { return 0; }
+int main (int argc, char *argv[])
 {
+  long double (*my_roundl) (long double) = argc ? roundl : dummy;
+  int result = 0;
   /* Test whether roundl (-0.0L) is -0.0L.  */
-  if (signbitl (minus_zerol) && !signbitl (roundl (minus_zerol)))
-    return 1;
-  return 0;
+  if (signbitl (minus_zerol) && !signbitl (my_roundl (minus_zerol)))
+    result |= 1;
+  /* Test whether roundl (-0.3L) is -0.0L.  */
+  if (signbitl (-0.3L) && !signbitl (my_roundl (-0.3L)))
+    result |= 2;
+  return result;
 }
               ]])],
               [gl_cv_func_roundl_ieee=yes],
               [gl_cv_func_roundl_ieee=no],
-              [gl_cv_func_roundl_ieee="guessing no"])
+              [case "$host_os" in
+                         # Guess yes on glibc systems.
+                 *-gnu*) gl_cv_func_roundl_ieee="guessing yes" ;;
+                         # If we don't know, assume the worst.
+                 *)      gl_cv_func_roundl_ieee="guessing no" ;;
+               esac
+              ])
             LIBS="$save_LIBS"
           ])
         case "$gl_cv_func_roundl_ieee" in
@@ -51,34 +79,40 @@ int main()
       fi
     ])
   else
+    HAVE_ROUNDL=0
     HAVE_DECL_ROUNDL=0
   fi
-  if test $HAVE_DECL_ROUNDL = 0 || test $REPLACE_ROUNDL = 1; then
-    AC_LIBOBJ([roundl])
-    AC_CHECK_DECLS([ceill, floorl], , , [#include <math.h>])
-    if test "$ac_cv_have_decl_floorl" = yes \
-       && test "$ac_cv_have_decl_ceill" = yes; then
-      gl_FUNC_FLOORL_LIBS
-      gl_FUNC_CEILL_LIBS
-      if test "$FLOORL_LIBM" != '?' && test "$CEILL_LIBM" != '?'; then
-        AC_DEFINE([HAVE_FLOORL_AND_CEILL], [1],
-          [Define if the both the floorl() and ceill() functions exist.])
-        ROUNDL_LIBM=
-        dnl Append $FLOORL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
-        case " $ROUNDL_LIBM " in
-          *" $FLOORL_LIBM "*) ;;
-          *) ROUNDL_LIBM="$ROUNDL_LIBM $FLOORL_LIBM" ;;
-        esac
-        dnl Append $CEILL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
-        case " $ROUNDL_LIBM " in
-          *" $CEILL_LIBM "*) ;;
-          *) ROUNDL_LIBM="$ROUNDL_LIBM $CEILL_LIBM" ;;
-        esac
+  if test $HAVE_ROUNDL = 0 || test $REPLACE_ROUNDL = 1; then
+    dnl Find libraries needed to link lib/roundl.c.
+    if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+      AC_REQUIRE([gl_FUNC_ROUND])
+      ROUNDL_LIBM="$ROUND_LIBM"
+    else
+      AC_CHECK_DECLS([ceill, floorl], , , [[#include <math.h>]])
+      if test "$ac_cv_have_decl_floorl" = yes \
+         && test "$ac_cv_have_decl_ceill" = yes; then
+        gl_FUNC_FLOORL_LIBS
+        gl_FUNC_CEILL_LIBS
+        if test "$FLOORL_LIBM" != '?' && test "$CEILL_LIBM" != '?'; then
+          AC_DEFINE([HAVE_FLOORL_AND_CEILL], [1],
+            [Define if the both the floorl() and ceill() functions exist.])
+          ROUNDL_LIBM=
+          dnl Append $FLOORL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
+          case " $ROUNDL_LIBM " in
+            *" $FLOORL_LIBM "*) ;;
+            *) ROUNDL_LIBM="$ROUNDL_LIBM $FLOORL_LIBM" ;;
+          esac
+          dnl Append $CEILL_LIBM to ROUNDL_LIBM, avoiding gratuitous duplicates.
+          case " $ROUNDL_LIBM " in
+            *" $CEILL_LIBM "*) ;;
+            *) ROUNDL_LIBM="$ROUNDL_LIBM $CEILL_LIBM" ;;
+          esac
+        else
+          ROUNDL_LIBM=
+        fi
       else
         ROUNDL_LIBM=
       fi
-    else
-      ROUNDL_LIBM=
     fi
   fi
   AC_SUBST([ROUNDL_LIBM])