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* build-aux/gendocs.sh (version): * doc/gendocs_template: * doc/gendocs_template_min: * doc/gnulib.texi: * lib/version-etc.c (COPYRIGHT_YEAR): Update copyright dates by hand in templates and the like. * all files: Run 'make update-copyright'.
82 lines
2.4 KiB
Plaintext
82 lines
2.4 KiB
Plaintext
# logbf.m4 serial 1
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dnl Copyright (C) 2012-2017 Free Software Foundation, Inc.
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dnl This file is free software; the Free Software Foundation
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dnl gives unlimited permission to copy and/or distribute it,
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dnl with or without modifications, as long as this notice is preserved.
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AC_DEFUN([gl_FUNC_LOGBF],
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[
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AC_REQUIRE([gl_MATH_H_DEFAULTS])
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dnl Persuade glibc <math.h> to declare logbf().
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AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
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dnl Determine LOGBF_LIBM.
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gl_MATHFUNC([logbf], [float], [(float)])
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if test $gl_cv_func_logbf_no_libm = yes \
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|| test $gl_cv_func_logbf_in_libm = yes; then
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save_LIBS="$LIBS"
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LIBS="$LIBS $LOGBF_LIBM"
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gl_FUNC_LOGBF_WORKS
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LIBS="$save_LIBS"
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case "$gl_cv_func_logbf_works" in
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*yes) ;;
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*) REPLACE_LOGBF=1 ;;
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esac
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else
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HAVE_LOGBF=0
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fi
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if test $HAVE_LOGBF = 0 || test $REPLACE_LOGBF = 1; then
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dnl Find libraries needed to link lib/logbf.c.
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AC_REQUIRE([gl_FUNC_FREXPF])
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AC_REQUIRE([gl_FUNC_ISNANF])
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LOGBF_LIBM=
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dnl Append $FREXPF_LIBM to LOGBF_LIBM, avoiding gratuitous duplicates.
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case " $LOGBF_LIBM " in
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*" $FREXPF_LIBM "*) ;;
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*) LOGBF_LIBM="$LOGBF_LIBM $FREXPF_LIBM" ;;
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esac
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dnl Append $ISNANF_LIBM to LOGBF_LIBM, avoiding gratuitous duplicates.
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case " $LOGBF_LIBM " in
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*" $ISNANF_LIBM "*) ;;
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*) LOGBF_LIBM="$LOGBF_LIBM $ISNANF_LIBM" ;;
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esac
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fi
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AC_SUBST([LOGBF_LIBM])
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])
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dnl Test whether logbf() works.
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dnl On glibc 2.11/ppc, glibc 2.7/sparc, glibc 2.7/hppa, Solaris 10/SPARC,
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dnl the return value for subnormal (denormalized) arguments is too large.
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AC_DEFUN([gl_FUNC_LOGBF_WORKS],
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[
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AC_REQUIRE([AC_PROG_CC])
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AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
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AC_CACHE_CHECK([whether logbf works], [gl_cv_func_logbf_works],
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[
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AC_RUN_IFELSE(
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[AC_LANG_SOURCE([[
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#include <float.h>
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#include <math.h>
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volatile float x;
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int main ()
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{
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int i;
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for (i = 1, x = 1.0f; i >= FLT_MIN_EXP; i--, x *= 0.5f)
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;
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/* Here i = FLT_MIN_EXP - 1. Either x = 2^(i-1) is subnormal or x = 0.0. */
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if (x > 0.0f && !(logbf (x) == (float)(i - 1)))
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return 1;
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return 0;
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}
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]])],
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[gl_cv_func_logbf_works=yes],
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[gl_cv_func_logbf_works=no],
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[case "$host_os" in
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*gnu* | solaris*) gl_cv_func_logbf_works="guessing no";;
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*) gl_cv_func_logbf_works="guessing yes";;
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esac
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])
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])
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])
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