-# log1pl.m4 serial 1
-dnl Copyright (C) 2012 Free Software Foundation, Inc.
+# log1pl.m4 serial 3
+dnl Copyright (C) 2012-2013 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.
AC_DEFUN([gl_FUNC_LOG1PL],
[
+ m4_divert_text([DEFAULTS], [gl_log1pl_required=plain])
AC_REQUIRE([gl_MATH_H_DEFAULTS])
AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
AC_REQUIRE([gl_FUNC_LOG1P])
LIBS="$save_LIBS"
if test $ac_cv_func_log1pl = yes; then
LOG1PL_LIBM="$LOG1P_LIBM"
+ m4_ifdef([gl_FUNC_LOG1PL_IEEE], [
+ if test $gl_log1pl_required = ieee && test $REPLACE_LOG1PL = 0; then
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+ AC_CACHE_CHECK([whether log1pl works according to ISO C 99 with IEC 60559],
+ [gl_cv_func_log1pl_ieee],
+ [
+ save_LIBS="$LIBS"
+ LIBS="$LIBS $LOG1PL_LIBM"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#ifndef __NO_MATH_INLINES
+# define __NO_MATH_INLINES 1 /* for glibc */
+#endif
+#include <math.h>
+]gl_LONG_DOUBLE_MINUS_ZERO_CODE[
+]gl_LONG_DOUBLE_SIGNBIT_CODE[
+static long double dummy (long double x) { return 0; }
+int main (int argc, char *argv[])
+{
+ long double (*my_log1pl) (long double) = argc ? log1pl : dummy;
+ /* This test fails on AIX 7.1, IRIX 6.5. */
+ long double y = my_log1pl (minus_zerol);
+ if (!(y == 0.0L) || (signbitl (minus_zerol) && !signbitl (y)))
+ return 1;
+ return 0;
+}
+ ]])],
+ [gl_cv_func_log1pl_ieee=yes],
+ [gl_cv_func_log1pl_ieee=no],
+ [case "$host_os" in
+ # Guess yes on glibc systems.
+ *-gnu*) gl_cv_func_log1pl_ieee="guessing yes" ;;
+ # If we don't know, assume the worst.
+ *) gl_cv_func_log1pl_ieee="guessing no" ;;
+ esac
+ ])
+ LIBS="$save_LIBS"
+ ])
+ case "$gl_cv_func_log1pl_ieee" in
+ *yes) ;;
+ *) REPLACE_LOG1PL=1 ;;
+ esac
+ fi
+ ])
else
HAVE_LOG1PL=0
dnl Find libraries needed to link lib/log1pl.c.