commit 1e68bbe1da86913820af146ec5294d1ab53d72f7
Author: Detlef Vollmann <dv@vollmann.ch>
Date:   Sat Jun 15 00:19:45 2024 +0200

    libstdc++-v3: detect math functions when using avr-libc and handle macros
    
    Different versions of avr-libc have different definitions of
    math functions:
      - 2.0.0 and earlier have float versions as macros
      - 2.1.0 has float versions as proper functions, but no long double versions
      - 2.2.0 has long double versions
    
    This commit tells configure to always check if these functions are available.
    It also #undef's any macros.
    
    libstdc++-v3/ChangeLog:
    
            * crossconfig.m4 [avr*-*-*]: Add compile-checks for
            float and long double functions.
            * configure: Regenerate.
            * src/c++98/math_stubs_float.cc: #undef any macros.

diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 5645e991af7..891a5f8e053 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -28628,51 +28628,2354 @@ case "${host}" in
     ;;
 
   avr*-*-*)
-    $as_echo "#define HAVE_ACOSF 1" >>confdefs.h
 
-    $as_echo "#define HAVE_ASINF 1" >>confdefs.h
 
-    $as_echo "#define HAVE_ATAN2F 1" >>confdefs.h
 
-    $as_echo "#define HAVE_ATANF 1" >>confdefs.h
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for acosf declaration" >&5
+$as_echo_n "checking for acosf declaration... " >&6; }
+if ${glibcxx_cv_func_acosf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef acosf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))acosf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_acosf_use=yes
+
+else
+  glibcxx_cv_func_acosf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_acosf_use" >&5
+$as_echo "$glibcxx_cv_func_acosf_use" >&6; }
+  if test "x$glibcxx_cv_func_acosf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ACOSF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for asinf declaration" >&5
+$as_echo_n "checking for asinf declaration... " >&6; }
+if ${glibcxx_cv_func_asinf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef asinf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))asinf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_asinf_use=yes
+
+else
+  glibcxx_cv_func_asinf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_asinf_use" >&5
+$as_echo "$glibcxx_cv_func_asinf_use" >&6; }
+  if test "x$glibcxx_cv_func_asinf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ASINF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for atan2f declaration" >&5
+$as_echo_n "checking for atan2f declaration... " >&6; }
+if ${glibcxx_cv_func_atan2f_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef atan2f
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))atan2f;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_atan2f_use=yes
+
+else
+  glibcxx_cv_func_atan2f_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_atan2f_use" >&5
+$as_echo "$glibcxx_cv_func_atan2f_use" >&6; }
+  if test "x$glibcxx_cv_func_atan2f_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ATAN2F 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for atanf declaration" >&5
+$as_echo_n "checking for atanf declaration... " >&6; }
+if ${glibcxx_cv_func_atanf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef atanf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))atanf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_atanf_use=yes
+
+else
+  glibcxx_cv_func_atanf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_atanf_use" >&5
+$as_echo "$glibcxx_cv_func_atanf_use" >&6; }
+  if test "x$glibcxx_cv_func_atanf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ATANF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ceilf declaration" >&5
+$as_echo_n "checking for ceilf declaration... " >&6; }
+if ${glibcxx_cv_func_ceilf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef ceilf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))ceilf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_ceilf_use=yes
+
+else
+  glibcxx_cv_func_ceilf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_ceilf_use" >&5
+$as_echo "$glibcxx_cv_func_ceilf_use" >&6; }
+  if test "x$glibcxx_cv_func_ceilf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_CEILF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for coshf declaration" >&5
+$as_echo_n "checking for coshf declaration... " >&6; }
+if ${glibcxx_cv_func_coshf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef coshf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))coshf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_coshf_use=yes
+
+else
+  glibcxx_cv_func_coshf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_coshf_use" >&5
+$as_echo "$glibcxx_cv_func_coshf_use" >&6; }
+  if test "x$glibcxx_cv_func_coshf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_COSHF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for cosf declaration" >&5
+$as_echo_n "checking for cosf declaration... " >&6; }
+if ${glibcxx_cv_func_cosf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef cosf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))cosf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_cosf_use=yes
+
+else
+  glibcxx_cv_func_cosf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_cosf_use" >&5
+$as_echo "$glibcxx_cv_func_cosf_use" >&6; }
+  if test "x$glibcxx_cv_func_cosf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_COSF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for expf declaration" >&5
+$as_echo_n "checking for expf declaration... " >&6; }
+if ${glibcxx_cv_func_expf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef expf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))expf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_expf_use=yes
+
+else
+  glibcxx_cv_func_expf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_expf_use" >&5
+$as_echo "$glibcxx_cv_func_expf_use" >&6; }
+  if test "x$glibcxx_cv_func_expf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_EXPF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for fabsf declaration" >&5
+$as_echo_n "checking for fabsf declaration... " >&6; }
+if ${glibcxx_cv_func_fabsf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef fabsf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))fabsf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_fabsf_use=yes
+
+else
+  glibcxx_cv_func_fabsf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_fabsf_use" >&5
+$as_echo "$glibcxx_cv_func_fabsf_use" >&6; }
+  if test "x$glibcxx_cv_func_fabsf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FABSF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for floorf declaration" >&5
+$as_echo_n "checking for floorf declaration... " >&6; }
+if ${glibcxx_cv_func_floorf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef floorf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))floorf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_floorf_use=yes
+
+else
+  glibcxx_cv_func_floorf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_floorf_use" >&5
+$as_echo "$glibcxx_cv_func_floorf_use" >&6; }
+  if test "x$glibcxx_cv_func_floorf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FLOORF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for fmodf declaration" >&5
+$as_echo_n "checking for fmodf declaration... " >&6; }
+if ${glibcxx_cv_func_fmodf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef fmodf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))fmodf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_fmodf_use=yes
+
+else
+  glibcxx_cv_func_fmodf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_fmodf_use" >&5
+$as_echo "$glibcxx_cv_func_fmodf_use" >&6; }
+  if test "x$glibcxx_cv_func_fmodf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FMODF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for frexpf declaration" >&5
+$as_echo_n "checking for frexpf declaration... " >&6; }
+if ${glibcxx_cv_func_frexpf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef frexpf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))frexpf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_frexpf_use=yes
+
+else
+  glibcxx_cv_func_frexpf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_frexpf_use" >&5
+$as_echo "$glibcxx_cv_func_frexpf_use" >&6; }
+  if test "x$glibcxx_cv_func_frexpf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FREXPF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for hypotf declaration" >&5
+$as_echo_n "checking for hypotf declaration... " >&6; }
+if ${glibcxx_cv_func_hypotf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef hypotf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))hypotf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_hypotf_use=yes
+
+else
+  glibcxx_cv_func_hypotf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_hypotf_use" >&5
+$as_echo "$glibcxx_cv_func_hypotf_use" >&6; }
+  if test "x$glibcxx_cv_func_hypotf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_HYPOTF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ldexpf declaration" >&5
+$as_echo_n "checking for ldexpf declaration... " >&6; }
+if ${glibcxx_cv_func_ldexpf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef ldexpf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))ldexpf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_ldexpf_use=yes
+
+else
+  glibcxx_cv_func_ldexpf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_ldexpf_use" >&5
+$as_echo "$glibcxx_cv_func_ldexpf_use" >&6; }
+  if test "x$glibcxx_cv_func_ldexpf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_LDEXPF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for log10f declaration" >&5
+$as_echo_n "checking for log10f declaration... " >&6; }
+if ${glibcxx_cv_func_log10f_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef log10f
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))log10f;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_log10f_use=yes
+
+else
+  glibcxx_cv_func_log10f_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_log10f_use" >&5
+$as_echo "$glibcxx_cv_func_log10f_use" >&6; }
+  if test "x$glibcxx_cv_func_log10f_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_LOG10F 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for logf declaration" >&5
+$as_echo_n "checking for logf declaration... " >&6; }
+if ${glibcxx_cv_func_logf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef logf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))logf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_logf_use=yes
+
+else
+  glibcxx_cv_func_logf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_logf_use" >&5
+$as_echo "$glibcxx_cv_func_logf_use" >&6; }
+  if test "x$glibcxx_cv_func_logf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_LOGF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for modff declaration" >&5
+$as_echo_n "checking for modff declaration... " >&6; }
+if ${glibcxx_cv_func_modff_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef modff
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))modff;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_modff_use=yes
+
+else
+  glibcxx_cv_func_modff_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_modff_use" >&5
+$as_echo "$glibcxx_cv_func_modff_use" >&6; }
+  if test "x$glibcxx_cv_func_modff_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_MODFF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for powf declaration" >&5
+$as_echo_n "checking for powf declaration... " >&6; }
+if ${glibcxx_cv_func_powf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef powf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))powf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_powf_use=yes
+
+else
+  glibcxx_cv_func_powf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_powf_use" >&5
+$as_echo "$glibcxx_cv_func_powf_use" >&6; }
+  if test "x$glibcxx_cv_func_powf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_POWF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sinhf declaration" >&5
+$as_echo_n "checking for sinhf declaration... " >&6; }
+if ${glibcxx_cv_func_sinhf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef sinhf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))sinhf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_sinhf_use=yes
+
+else
+  glibcxx_cv_func_sinhf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_sinhf_use" >&5
+$as_echo "$glibcxx_cv_func_sinhf_use" >&6; }
+  if test "x$glibcxx_cv_func_sinhf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_SINHF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sinf declaration" >&5
+$as_echo_n "checking for sinf declaration... " >&6; }
+if ${glibcxx_cv_func_sinf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef sinf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))sinf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_sinf_use=yes
+
+else
+  glibcxx_cv_func_sinf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_sinf_use" >&5
+$as_echo "$glibcxx_cv_func_sinf_use" >&6; }
+  if test "x$glibcxx_cv_func_sinf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_SINF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sqrtf declaration" >&5
+$as_echo_n "checking for sqrtf declaration... " >&6; }
+if ${glibcxx_cv_func_sqrtf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef sqrtf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))sqrtf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_sqrtf_use=yes
+
+else
+  glibcxx_cv_func_sqrtf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_sqrtf_use" >&5
+$as_echo "$glibcxx_cv_func_sqrtf_use" >&6; }
+  if test "x$glibcxx_cv_func_sqrtf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_SQRTF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for tanhf declaration" >&5
+$as_echo_n "checking for tanhf declaration... " >&6; }
+if ${glibcxx_cv_func_tanhf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef tanhf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))tanhf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_tanhf_use=yes
+
+else
+  glibcxx_cv_func_tanhf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_tanhf_use" >&5
+$as_echo "$glibcxx_cv_func_tanhf_use" >&6; }
+  if test "x$glibcxx_cv_func_tanhf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_TANHF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for tanf declaration" >&5
+$as_echo_n "checking for tanf declaration... " >&6; }
+if ${glibcxx_cv_func_tanf_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef tanf
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))tanf;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_tanf_use=yes
+
+else
+  glibcxx_cv_func_tanf_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_tanf_use" >&5
+$as_echo "$glibcxx_cv_func_tanf_use" >&6; }
+  if test "x$glibcxx_cv_func_tanf_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_TANF 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for acosl declaration" >&5
+$as_echo_n "checking for acosl declaration... " >&6; }
+if ${glibcxx_cv_func_acosl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef acosl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))acosl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_acosl_use=yes
+
+else
+  glibcxx_cv_func_acosl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_acosl_use" >&5
+$as_echo "$glibcxx_cv_func_acosl_use" >&6; }
+  if test "x$glibcxx_cv_func_acosl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ACOSL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for asinl declaration" >&5
+$as_echo_n "checking for asinl declaration... " >&6; }
+if ${glibcxx_cv_func_asinl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef asinl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))asinl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_asinl_use=yes
+
+else
+  glibcxx_cv_func_asinl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_asinl_use" >&5
+$as_echo "$glibcxx_cv_func_asinl_use" >&6; }
+  if test "x$glibcxx_cv_func_asinl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ASINL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for atan2l declaration" >&5
+$as_echo_n "checking for atan2l declaration... " >&6; }
+if ${glibcxx_cv_func_atan2l_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef atan2l
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))atan2l;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_atan2l_use=yes
+
+else
+  glibcxx_cv_func_atan2l_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_atan2l_use" >&5
+$as_echo "$glibcxx_cv_func_atan2l_use" >&6; }
+  if test "x$glibcxx_cv_func_atan2l_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ATAN2L 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for atanl declaration" >&5
+$as_echo_n "checking for atanl declaration... " >&6; }
+if ${glibcxx_cv_func_atanl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef atanl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))atanl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_atanl_use=yes
+
+else
+  glibcxx_cv_func_atanl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_atanl_use" >&5
+$as_echo "$glibcxx_cv_func_atanl_use" >&6; }
+  if test "x$glibcxx_cv_func_atanl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_ATANL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ceill declaration" >&5
+$as_echo_n "checking for ceill declaration... " >&6; }
+if ${glibcxx_cv_func_ceill_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef ceill
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))ceill;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_ceill_use=yes
+
+else
+  glibcxx_cv_func_ceill_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_ceill_use" >&5
+$as_echo "$glibcxx_cv_func_ceill_use" >&6; }
+  if test "x$glibcxx_cv_func_ceill_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_CEILL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for coshl declaration" >&5
+$as_echo_n "checking for coshl declaration... " >&6; }
+if ${glibcxx_cv_func_coshl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef coshl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))coshl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_coshl_use=yes
+
+else
+  glibcxx_cv_func_coshl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_coshl_use" >&5
+$as_echo "$glibcxx_cv_func_coshl_use" >&6; }
+  if test "x$glibcxx_cv_func_coshl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_COSHL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for cosl declaration" >&5
+$as_echo_n "checking for cosl declaration... " >&6; }
+if ${glibcxx_cv_func_cosl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef cosl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))cosl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_cosl_use=yes
+
+else
+  glibcxx_cv_func_cosl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_cosl_use" >&5
+$as_echo "$glibcxx_cv_func_cosl_use" >&6; }
+  if test "x$glibcxx_cv_func_cosl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_COSL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for expl declaration" >&5
+$as_echo_n "checking for expl declaration... " >&6; }
+if ${glibcxx_cv_func_expl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef expl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))expl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_expl_use=yes
+
+else
+  glibcxx_cv_func_expl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_expl_use" >&5
+$as_echo "$glibcxx_cv_func_expl_use" >&6; }
+  if test "x$glibcxx_cv_func_expl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_EXPL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for fabsl declaration" >&5
+$as_echo_n "checking for fabsl declaration... " >&6; }
+if ${glibcxx_cv_func_fabsl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef fabsl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))fabsl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_fabsl_use=yes
+
+else
+  glibcxx_cv_func_fabsl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_fabsl_use" >&5
+$as_echo "$glibcxx_cv_func_fabsl_use" >&6; }
+  if test "x$glibcxx_cv_func_fabsl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FABSL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for floorl declaration" >&5
+$as_echo_n "checking for floorl declaration... " >&6; }
+if ${glibcxx_cv_func_floorl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef floorl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))floorl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_floorl_use=yes
+
+else
+  glibcxx_cv_func_floorl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_floorl_use" >&5
+$as_echo "$glibcxx_cv_func_floorl_use" >&6; }
+  if test "x$glibcxx_cv_func_floorl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FLOORL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for fmodl declaration" >&5
+$as_echo_n "checking for fmodl declaration... " >&6; }
+if ${glibcxx_cv_func_fmodl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef fmodl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))fmodl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_fmodl_use=yes
+
+else
+  glibcxx_cv_func_fmodl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_fmodl_use" >&5
+$as_echo "$glibcxx_cv_func_fmodl_use" >&6; }
+  if test "x$glibcxx_cv_func_fmodl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FMODL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for frexpl declaration" >&5
+$as_echo_n "checking for frexpl declaration... " >&6; }
+if ${glibcxx_cv_func_frexpl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef frexpl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))frexpl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_frexpl_use=yes
+
+else
+  glibcxx_cv_func_frexpl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_frexpl_use" >&5
+$as_echo "$glibcxx_cv_func_frexpl_use" >&6; }
+  if test "x$glibcxx_cv_func_frexpl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_FREXPL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for hypotl declaration" >&5
+$as_echo_n "checking for hypotl declaration... " >&6; }
+if ${glibcxx_cv_func_hypotl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef hypotl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))hypotl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_hypotl_use=yes
+
+else
+  glibcxx_cv_func_hypotl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_hypotl_use" >&5
+$as_echo "$glibcxx_cv_func_hypotl_use" >&6; }
+  if test "x$glibcxx_cv_func_hypotl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_HYPOTL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ldexpl declaration" >&5
+$as_echo_n "checking for ldexpl declaration... " >&6; }
+if ${glibcxx_cv_func_ldexpl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef ldexpl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))ldexpl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_ldexpl_use=yes
+
+else
+  glibcxx_cv_func_ldexpl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_ldexpl_use" >&5
+$as_echo "$glibcxx_cv_func_ldexpl_use" >&6; }
+  if test "x$glibcxx_cv_func_ldexpl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_LDEXPL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for log10l declaration" >&5
+$as_echo_n "checking for log10l declaration... " >&6; }
+if ${glibcxx_cv_func_log10l_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef log10l
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))log10l;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_log10l_use=yes
+
+else
+  glibcxx_cv_func_log10l_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_log10l_use" >&5
+$as_echo "$glibcxx_cv_func_log10l_use" >&6; }
+  if test "x$glibcxx_cv_func_log10l_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_LOG10L 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for logl declaration" >&5
+$as_echo_n "checking for logl declaration... " >&6; }
+if ${glibcxx_cv_func_logl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef logl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))logl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_logl_use=yes
+
+else
+  glibcxx_cv_func_logl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_logl_use" >&5
+$as_echo "$glibcxx_cv_func_logl_use" >&6; }
+  if test "x$glibcxx_cv_func_logl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_LOGL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for modfl declaration" >&5
+$as_echo_n "checking for modfl declaration... " >&6; }
+if ${glibcxx_cv_func_modfl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef modfl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))modfl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_modfl_use=yes
+
+else
+  glibcxx_cv_func_modfl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_modfl_use" >&5
+$as_echo "$glibcxx_cv_func_modfl_use" >&6; }
+  if test "x$glibcxx_cv_func_modfl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_MODFL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for powl declaration" >&5
+$as_echo_n "checking for powl declaration... " >&6; }
+if ${glibcxx_cv_func_powl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef powl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))powl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_powl_use=yes
+
+else
+  glibcxx_cv_func_powl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_powl_use" >&5
+$as_echo "$glibcxx_cv_func_powl_use" >&6; }
+  if test "x$glibcxx_cv_func_powl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_POWL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sinhl declaration" >&5
+$as_echo_n "checking for sinhl declaration... " >&6; }
+if ${glibcxx_cv_func_sinhl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
 
-    $as_echo "#define HAVE_CEILF 1" >>confdefs.h
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
-    $as_echo "#define HAVE_COSF 1" >>confdefs.h
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
 
-    $as_echo "#define HAVE_COSHF 1" >>confdefs.h
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef sinhl
 
-    $as_echo "#define HAVE_EXPF 1" >>confdefs.h
+int
+main ()
+{
 
-    $as_echo "#define HAVE_FABSF 1" >>confdefs.h
+  void (*f)(void) = (void (*)(void))sinhl;
 
-    $as_echo "#define HAVE_FLOORF 1" >>confdefs.h
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_sinhl_use=yes
 
-    $as_echo "#define HAVE_FMODF 1" >>confdefs.h
+else
+  glibcxx_cv_func_sinhl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_sinhl_use" >&5
+$as_echo "$glibcxx_cv_func_sinhl_use" >&6; }
+  if test "x$glibcxx_cv_func_sinhl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_SINHL 1
+_ACEOF
 
-    $as_echo "#define HAVE_FREXPF 1" >>confdefs.h
+  fi
 
-    $as_echo "#define HAVE_SQRTF 1" >>confdefs.h
 
-    $as_echo "#define HAVE_HYPOTF 1" >>confdefs.h
 
-    $as_echo "#define HAVE_LDEXPF 1" >>confdefs.h
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sinl declaration" >&5
+$as_echo_n "checking for sinl declaration... " >&6; }
+if ${glibcxx_cv_func_sinl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
 
-    $as_echo "#define HAVE_LOG10F 1" >>confdefs.h
 
-    $as_echo "#define HAVE_LOGF 1" >>confdefs.h
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
-    $as_echo "#define HAVE_MODFF 1" >>confdefs.h
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
 
-    $as_echo "#define HAVE_POWF 1" >>confdefs.h
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef sinl
 
-    $as_echo "#define HAVE_SINF 1" >>confdefs.h
+int
+main ()
+{
 
-    $as_echo "#define HAVE_SINHF 1" >>confdefs.h
+  void (*f)(void) = (void (*)(void))sinl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_sinl_use=yes
+
+else
+  glibcxx_cv_func_sinl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_sinl_use" >&5
+$as_echo "$glibcxx_cv_func_sinl_use" >&6; }
+  if test "x$glibcxx_cv_func_sinl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_SINL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for sqrtl declaration" >&5
+$as_echo_n "checking for sqrtl declaration... " >&6; }
+if ${glibcxx_cv_func_sqrtl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef sqrtl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))sqrtl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_sqrtl_use=yes
+
+else
+  glibcxx_cv_func_sqrtl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_sqrtl_use" >&5
+$as_echo "$glibcxx_cv_func_sqrtl_use" >&6; }
+  if test "x$glibcxx_cv_func_sqrtl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_SQRTL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for tanhl declaration" >&5
+$as_echo_n "checking for tanhl declaration... " >&6; }
+if ${glibcxx_cv_func_tanhl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef tanhl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))tanhl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_tanhl_use=yes
+
+else
+  glibcxx_cv_func_tanhl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_tanhl_use" >&5
+$as_echo "$glibcxx_cv_func_tanhl_use" >&6; }
+  if test "x$glibcxx_cv_func_tanhl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_TANHL 1
+_ACEOF
+
+  fi
+
+
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for tanl declaration" >&5
+$as_echo_n "checking for tanl declaration... " >&6; }
+if ${glibcxx_cv_func_tanl_use+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+
+      ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <math.h>
+#ifdef HAVE_IEEEFP_H
+# include <ieeefp.h>
+#endif
+#undef tanl
+
+int
+main ()
+{
+
+  void (*f)(void) = (void (*)(void))tanl;
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  glibcxx_cv_func_tanl_use=yes
+
+else
+  glibcxx_cv_func_tanl_use=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_func_tanl_use" >&5
+$as_echo "$glibcxx_cv_func_tanl_use" >&6; }
+  if test "x$glibcxx_cv_func_tanl_use" = xyes; then
+    cat >>confdefs.h <<_ACEOF
+#define HAVE_TANL 1
+_ACEOF
+
+  fi
 
-    $as_echo "#define HAVE_TANF 1" >>confdefs.h
 
-    $as_echo "#define HAVE_TANHF 1" >>confdefs.h
 
     ;;
 
diff --git a/libstdc++-v3/crossconfig.m4 b/libstdc++-v3/crossconfig.m4
index b3269cb88e0..5e1249d0a54 100644
--- a/libstdc++-v3/crossconfig.m4
+++ b/libstdc++-v3/crossconfig.m4
@@ -10,29 +10,16 @@ case "${host}" in
     ;;
 
   avr*-*-*)
-    AC_DEFINE(HAVE_ACOSF)
-    AC_DEFINE(HAVE_ASINF)
-    AC_DEFINE(HAVE_ATAN2F)
-    AC_DEFINE(HAVE_ATANF)
-    AC_DEFINE(HAVE_CEILF)
-    AC_DEFINE(HAVE_COSF)
-    AC_DEFINE(HAVE_COSHF)
-    AC_DEFINE(HAVE_EXPF)
-    AC_DEFINE(HAVE_FABSF)
-    AC_DEFINE(HAVE_FLOORF)
-    AC_DEFINE(HAVE_FMODF)
-    AC_DEFINE(HAVE_FREXPF)
-    AC_DEFINE(HAVE_SQRTF)
-    AC_DEFINE(HAVE_HYPOTF)
-    AC_DEFINE(HAVE_LDEXPF)
-    AC_DEFINE(HAVE_LOG10F)
-    AC_DEFINE(HAVE_LOGF)
-    AC_DEFINE(HAVE_MODFF)
-    AC_DEFINE(HAVE_POWF)
-    AC_DEFINE(HAVE_SINF)
-    AC_DEFINE(HAVE_SINHF)
-    AC_DEFINE(HAVE_TANF)
-    AC_DEFINE(HAVE_TANHF)
+dnl # Correct (non-macro) support for some math functions depends on
+dnl # newlib or avrlibc version.  So test for their availability
+dnl # rather than hardcoding that information.
+    GLIBCXX_CHECK_MATH_DECLS([
+      acosf asinf atan2f atanf ceilf coshf cosf expf fabsf floorf fmodf
+      frexpf hypotf ldexpf log10f logf modff powf sinhf sinf sqrtf
+      tanhf tanf
+      acosl asinl atan2l atanl ceill coshl cosl expl fabsl floorl fmodl
+      frexpl hypotl ldexpl log10l logl modfl powl sinhl sinl sqrtl
+      tanhl tanl])
     ;;
 
   mips*-sde-elf*)
diff --git a/libstdc++-v3/src/c++98/math_stubs_float.cc b/libstdc++-v3/src/c++98/math_stubs_float.cc
index 4dbe3afab8f..537bd4ae64e 100644
--- a/libstdc++-v3/src/c++98/math_stubs_float.cc
+++ b/libstdc++-v3/src/c++98/math_stubs_float.cc
@@ -31,6 +31,7 @@
 extern "C"
 {
 #ifndef _GLIBCXX_HAVE_FABSF
+#undef fabsf
   float
   fabsf(float x)
   {
@@ -39,6 +40,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_ACOSF
+#undef acosf
   float
   acosf(float x)
   {
@@ -47,6 +49,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_ASINF
+#undef asinf
   float
   asinf(float x)
   {
@@ -55,6 +58,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_ATANF
+#undef atanf
   float
   atanf(float x)
   {
@@ -63,6 +67,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_ATAN2F
+#undef atan2f
   float
   atan2f(float x, float y)
   {
@@ -71,6 +76,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_CEILF
+#undef ceilf
   float
   ceilf(float x)
   {
@@ -79,6 +85,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_COSF
+#undef cosf
   float
   cosf(float x)
   {
@@ -87,6 +94,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_COSHF
+#undef coshf
   float
   coshf(float x)
   {
@@ -95,6 +103,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_EXPF
+#undef expf
   float
   expf(float x)
   {
@@ -103,6 +112,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_FLOORF
+#undef floorf
   float
   floorf(float x)
   {
@@ -111,6 +121,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_FMODF
+#undef fmodf
   float
   fmodf(float x, float y)
   {
@@ -119,6 +130,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_FREXPF
+#undef frexpf
   float
   frexpf(float x, int *exp)
   {
@@ -127,6 +139,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_SQRTF
+#undef sqrtf
   float
   sqrtf(float x)
   {
@@ -135,6 +148,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_HYPOTF
+#undef hypotf
   float
   hypotf(float x, float y)
   {
@@ -147,6 +161,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_LDEXPF
+#undef ldexpf
   float
   ldexpf(float x, int exp)
   {
@@ -155,6 +170,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_LOGF
+#undef logf
   float
   logf(float x)
   {
@@ -163,6 +179,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_LOG10F
+#undef log10f
   float
   log10f(float x)
   {
@@ -171,6 +188,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_MODFF
+#undef modff
   float
   modff(float x, float *iptr)
   {
@@ -183,6 +201,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_POWF
+#undef powf
   float
   powf(float x, float y)
   {
@@ -191,6 +210,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_SINF
+#undef sinf
   float
   sinf(float x)
   {
@@ -199,6 +219,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_SINHF
+#undef sinhf
   float
   sinhf(float x)
   {
@@ -207,6 +228,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_TANF
+#undef tanf
   float
   tanf(float x)
   {
@@ -215,6 +237,7 @@ extern "C"
 #endif
 
 #ifndef _GLIBCXX_HAVE_TANHF
+#undef tanhf
   float
   tanhf(float x)
   {