remainderf-ieee: Work around test failure on OSF/1.

* m4/remainderf-ieee.m4: New file.
* m4/remainderf.m4 (gl_FUNC_REMAINDERF): If gl_FUNC_REMAINDERF_IEEE is
present, test whether remainderf works with a zero second argument.
Replace it if not.
* lib/math.in.h (remainderf): Override if REPLACE_REMAINDERF is 1.
* m4/math_h.m4 (gl_MATH_H_DEFAULTS): Initialize REPLACE_REMAINDERF.
* modules/math (Makefile.am): Substitute REPLACE_REMAINDERF.
* modules/remainderf (configure.ac): Consider REPLACE_REMAINDERF.
(Depends-on): Update conditions.
* modules/remainderf-ieee (Files): Add m4/remainderf-ieee.m4.
(Depends-on): Add remainder-ieee.
(configure.ac): Invoke gl_FUNC_REMAINDERF_IEEE.
* doc/posix-functions/remainderf.texi: Mention the remainderf-ieee
module.

9 files changed, 111 insertions, 10 deletions

diff --git a/ChangeLog b/ChangeLog
index 1696b92585..63dc9df28b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,21 @@
 2012-02-27  Bruno Haible  <bruno@clisp.org>
 
+	remainderf-ieee: Work around test failure on OSF/1.
+	* m4/remainderf-ieee.m4: New file.
+	* m4/remainderf.m4 (gl_FUNC_REMAINDERF): If gl_FUNC_REMAINDERF_IEEE is
+	present, test whether remainderf works with a zero second argument.
+	Replace it if not.
+	* lib/math.in.h (remainderf): Override if REPLACE_REMAINDERF is 1.
+	* m4/math_h.m4 (gl_MATH_H_DEFAULTS): Initialize REPLACE_REMAINDERF.
+	* modules/math (Makefile.am): Substitute REPLACE_REMAINDERF.
+	* modules/remainderf (configure.ac): Consider REPLACE_REMAINDERF.
+	(Depends-on): Update conditions.
+	* modules/remainderf-ieee (Files): Add m4/remainderf-ieee.m4.
+	(Depends-on): Add remainder-ieee.
+	(configure.ac): Invoke gl_FUNC_REMAINDERF_IEEE.
+	* doc/posix-functions/remainderf.texi: Mention the remainderf-ieee
+	module.
+
 	remainder-ieee: Work around test failure on OSF/1.
 	* m4/remainder-ieee.m4: New file.
 	* m4/remainder.m4 (gl_FUNC_REMAINDER): If gl_FUNC_REMAINDER_IEEE is
diff --git a/doc/posix-functions/remainderf.texi b/doc/posix-functions/remainderf.texi
index 7e2ddee104..22283190c7 100644
--- a/doc/posix-functions/remainderf.texi
+++ b/doc/posix-functions/remainderf.texi
@@ -4,15 +4,22 @@
 
 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/remainderf.html}
 
-Gnulib module: remainderf
+Gnulib module: remainderf or remainderf-ieee
 
-Portability problems fixed by Gnulib:
+Portability problems fixed by either Gnulib module @code{remainderf} or @code{remainderf-ieee}:
 @itemize
 @item
 This function is missing on some platforms:
 Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 9, MSVC 9.
 @end itemize
 
+Portability problems fixed by Gnulib module @code{remainderf-ieee}:
+@itemize
+@item
+This function has problems when the second argument is zero on some platforms:
+OSF/1 5.1.
+@end itemize
+
 Portability problems not fixed by Gnulib:
 @itemize
 @end itemize
diff --git a/lib/math.in.h b/lib/math.in.h
index bfee515d53..afd1b0a7d3 100644
--- a/lib/math.in.h
+++ b/lib/math.in.h
@@ -982,10 +982,19 @@ _GL_WARN_ON_USE (powf, "powf is unportable - "
 
 
 #if @GNULIB_REMAINDERF@
-# if !@HAVE_REMAINDERF@
+# if @REPLACE_REMAINDERF@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef remainderf
+#   define remainderf rpl_remainderf
+#  endif
+_GL_FUNCDECL_RPL (remainderf, float, (float x, float y));
+_GL_CXXALIAS_RPL (remainderf, float, (float x, float y));
+# else
+#  if !@HAVE_REMAINDERF@
 _GL_FUNCDECL_SYS (remainderf, float, (float x, float y));
-# endif
+#  endif
 _GL_CXXALIAS_SYS (remainderf, float, (float x, float y));
+# endif
 _GL_CXXALIASWARN (remainderf);
 #elif defined GNULIB_POSIXCHECK
 # undef remainderf
diff --git a/m4/math_h.m4 b/m4/math_h.m4
index 573daef936..e598ee1327 100644
--- a/m4/math_h.m4
+++ b/m4/math_h.m4
@@ -1,4 +1,4 @@
-# math_h.m4 serial 69
+# math_h.m4 serial 70
 dnl Copyright (C) 2007-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -229,6 +229,7 @@ AC_DEFUN([gl_MATH_H_DEFAULTS],
   REPLACE_MODFL=0;             AC_SUBST([REPLACE_MODFL])
   REPLACE_NAN=0;               AC_SUBST([REPLACE_NAN])
   REPLACE_REMAINDER=0;         AC_SUBST([REPLACE_REMAINDER])
+  REPLACE_REMAINDERF=0;        AC_SUBST([REPLACE_REMAINDERF])
   REPLACE_ROUND=0;             AC_SUBST([REPLACE_ROUND])
   REPLACE_ROUNDF=0;            AC_SUBST([REPLACE_ROUNDF])
   REPLACE_ROUNDL=0;            AC_SUBST([REPLACE_ROUNDL])
diff --git a/m4/remainderf-ieee.m4 b/m4/remainderf-ieee.m4
new file mode 100644
index 0000000000..f45c8e2dc1
--- /dev/null
+++ b/m4/remainderf-ieee.m4
@@ -0,0 +1,15 @@
+# remainderf-ieee.m4 serial 1
+dnl Copyright (C) 2012 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.
+
+dnl This macro is in a separate file (not in remainder.m4 and not inlined in the
+dnl module description), so that gl_FUNC_REMAINDERF can test whether 'aclocal'
+dnl has found uses of this macro.
+
+AC_DEFUN([gl_FUNC_REMAINDERF_IEEE],
+[
+  m4_divert_text([INIT_PREPARE], [gl_remainderf_required=ieee])
+  AC_REQUIRE([gl_FUNC_REMAINDERF])
+])
diff --git a/m4/remainderf.m4 b/m4/remainderf.m4
index 8134905350..4332bb946a 100644
--- a/m4/remainderf.m4
+++ b/m4/remainderf.m4
@@ -1,4 +1,4 @@
-# remainderf.m4 serial 1
+# remainderf.m4 serial 2
 dnl Copyright (C) 2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -6,6 +6,7 @@ dnl with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_FUNC_REMAINDERF],
 [
+  m4_divert_text([DEFAULTS], [gl_remainderf_required=plain])
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
   AC_REQUIRE([gl_FUNC_REMAINDER])
 
@@ -33,8 +34,56 @@ AC_DEFUN([gl_FUNC_REMAINDERF],
   LIBS="$save_LIBS"
   if test $gl_cv_func_remainderf = yes; then
     REMAINDERF_LIBM="$REMAINDER_LIBM"
+    m4_ifdef([gl_FUNC_REMAINDERF_IEEE], [
+      if test $gl_remainderf_required = ieee && test $REPLACE_REMAINDERF = 0; then
+        AC_CACHE_CHECK([whether remainderf works according to ISO C 99 with IEC 60559],
+          [gl_cv_func_remainderf_ieee],
+          [
+            save_LIBS="$LIBS"
+            LIBS="$LIBS $REMAINDERF_LIBM"
+            AC_RUN_IFELSE(
+              [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+/* Compare two numbers with ==.
+   This is a separate function because IRIX 6.5 "cc -O" miscompiles an
+   'x == x' test.  */
+static int
+numeric_equal (float x, float y)
+{
+  return x == y;
+}
+static float dummy (float x, float y) { return 0; }
+int main (int argc, char *argv[])
+{
+  float (*my_remainderf) (float, float) = argc ? remainderf : dummy;
+  float i;
+  float f;
+  /* Test remainderf(...,0.0f).
+     This test fails on OSF/1 5.1.  */
+  f = my_remainderf (2.0f, 0.0f);
+  if (numeric_equal (f, f))
+    return 1;
+  return 0;
+}
+              ]])],
+              [gl_cv_func_remainderf_ieee=yes],
+              [gl_cv_func_remainderf_ieee=no],
+              [gl_cv_func_remainderf_ieee="guessing no"])
+            LIBS="$save_LIBS"
+          ])
+        case "$gl_cv_func_remainderf_ieee" in
+          *yes) ;;
+          *) REPLACE_REMAINDERF=1 ;;
+        esac
+      fi
+    ])
   else
     HAVE_REMAINDERF=0
+  fi
+  if test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1; then
     dnl Find libraries needed to link lib/remainderf.c.
     if test $gl_cv_func_remainder_no_libm = yes \
        || test $gl_cv_func_remainder_in_libm = yes; then
diff --git a/modules/math b/modules/math
index 1efea00fdd..0f498242aa 100644
--- a/modules/math
+++ b/modules/math
@@ -199,6 +199,7 @@ math.h: math.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(
 	      -e 's|@''REPLACE_MODFL''@|$(REPLACE_MODFL)|g' \
 	      -e 's|@''REPLACE_NAN''@|$(REPLACE_NAN)|g' \
 	      -e 's|@''REPLACE_REMAINDER''@|$(REPLACE_REMAINDER)|g' \
+	      -e 's|@''REPLACE_REMAINDERF''@|$(REPLACE_REMAINDERF)|g' \
 	      -e 's|@''REPLACE_ROUND''@|$(REPLACE_ROUND)|g' \
 	      -e 's|@''REPLACE_ROUNDF''@|$(REPLACE_ROUNDF)|g' \
 	      -e 's|@''REPLACE_ROUNDL''@|$(REPLACE_ROUNDL)|g' \
diff --git a/modules/remainderf b/modules/remainderf
index 2f423b9a45..69a642621e 100644
--- a/modules/remainderf
+++ b/modules/remainderf
@@ -8,13 +8,13 @@ m4/mathfunc.m4
 
 Depends-on:
 math
-remainder       [test $HAVE_REMAINDERF = 0]
-roundf          [test $HAVE_REMAINDERF = 0]
-fmaf            [test $HAVE_REMAINDERF = 0]
+remainder       [test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1]
+roundf          [test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1]
+fmaf            [test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1]
 
 configure.ac:
 gl_FUNC_REMAINDERF
-if test $HAVE_REMAINDERF = 0; then
+if test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1; then
   AC_LIBOBJ([remainderf])
 fi
 gl_MATH_MODULE_INDICATOR([remainderf])
diff --git a/modules/remainderf-ieee b/modules/remainderf-ieee
index 52d10a187e..16f8dc4880 100644
--- a/modules/remainderf-ieee
+++ b/modules/remainderf-ieee
@@ -2,12 +2,15 @@ Description:
 remainderf() function according to ISO C 99 with IEC 60559.
 
 Files:
+m4/remainderf-ieee.m4
 
 Depends-on:
 remainderf
 fpieee
+remainder-ieee  [test $HAVE_REMAINDERF = 0 || test $REPLACE_REMAINDERF = 1]
 
 configure.ac:
+gl_FUNC_REMAINDERF_IEEE
 
 Makefile.am: