From 3c7a0ee522192719470c8836a964fc6175fa6c96 Mon Sep 17 00:00:00 2001 From: Bruno Haible Date: Sun, 11 Mar 2012 22:14:04 +0100 Subject: [PATCH] log2f-ieee: Work around test failure on NetBSD 5.1 and Solaris 10. * m4/log2f-ieee.m4: New file. * m4/log2f.m4 (gl_FUNC_LOG2F): If gl_FUNC_LOG2F_IEEE is present, test whether log2f works with a minus zero argument. Replace it if not. * modules/log2f-ieee (Files): Add m4/log2f-ieee.m4. (Depends-on): Add log2-ieee. (configure.ac): Invoke gl_FUNC_LOG2F_IEEE. * doc/posix-functions/log2f.texi: Mention the log2f-ieee module. --- ChangeLog | 9 +++++++ doc/posix-functions/log2f.texi | 11 +++++++-- m4/log2f-ieee.m4 | 15 ++++++++++++ m4/log2f.m4 | 55 +++++++++++++++++++++++++++++++++++++++++- modules/log2f-ieee | 3 +++ 5 files changed, 90 insertions(+), 3 deletions(-) create mode 100644 m4/log2f-ieee.m4 diff --git a/ChangeLog b/ChangeLog index e4963bd2d..e286b7324 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,14 @@ 2012-03-11 Bruno Haible + log2f-ieee: Work around test failure on NetBSD 5.1 and Solaris 10. + * m4/log2f-ieee.m4: New file. + * m4/log2f.m4 (gl_FUNC_LOG2F): If gl_FUNC_LOG2F_IEEE is present, test + whether log2f works with a minus zero argument. Replace it if not. + * modules/log2f-ieee (Files): Add m4/log2f-ieee.m4. + (Depends-on): Add log2-ieee. + (configure.ac): Invoke gl_FUNC_LOG2F_IEEE. + * doc/posix-functions/log2f.texi: Mention the log2f-ieee module. + log2-ieee: Work around test failure on NetBSD 5.1 and Solaris 10. * m4/log2-ieee.m4: New file. * m4/log2.m4 (gl_FUNC_LOG2): If gl_FUNC_LOG2_IEEE is present, test diff --git a/doc/posix-functions/log2f.texi b/doc/posix-functions/log2f.texi index ac6d18276..f137ed165 100644 --- a/doc/posix-functions/log2f.texi +++ b/doc/posix-functions/log2f.texi @@ -4,9 +4,9 @@ POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/log2f.html} -Gnulib module: log2f +Gnulib module: log2f or log2f-ieee -Portability problems fixed by Gnulib: +Portability problems fixed by either Gnulib module @code{log2f} or @code{log2f-ieee}: @itemize @item This function is missing on some platforms: @@ -26,6 +26,13 @@ This function returns slightly wrong values for exact powers of 2 on some platfo Cygwin 1.7.9. @end itemize +Portability problems fixed by Gnulib module @code{log2f-ieee}: +@itemize +@item +This function returns a wrong value for a negative argument on some platforms: +NetBSD 5.1, Solaris 11 2011-11. +@end itemize + Portability problems not fixed by Gnulib: @itemize @end itemize diff --git a/m4/log2f-ieee.m4 b/m4/log2f-ieee.m4 new file mode 100644 index 000000000..8b699eece --- /dev/null +++ b/m4/log2f-ieee.m4 @@ -0,0 +1,15 @@ +# log2f-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_LOG2F can test whether 'aclocal' has +dnl found uses of this macro. + +AC_DEFUN([gl_FUNC_LOG2F_IEEE], +[ + m4_divert_text([INIT_PREPARE], [gl_log2f_required=ieee]) + AC_REQUIRE([gl_FUNC_LOG2F]) +]) diff --git a/m4/log2f.m4 b/m4/log2f.m4 index 4ff32d8da..d9fffd0aa 100644 --- a/m4/log2f.m4 +++ b/m4/log2f.m4 @@ -1,4 +1,4 @@ -# log2f.m4 serial 1 +# log2f.m4 serial 2 dnl Copyright (C) 2010-2012 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_LOG2F], [ + m4_divert_text([DEFAULTS], [gl_log2f_required=plain]) AC_REQUIRE([gl_MATH_H_DEFAULTS]) AC_REQUIRE([gl_FUNC_LOG2]) @@ -34,6 +35,58 @@ AC_DEFUN([gl_FUNC_LOG2F], *yes) ;; *) REPLACE_LOG2F=1 ;; esac + + m4_ifdef([gl_FUNC_LOG2F_IEEE], [ + if test $gl_log2f_required = ieee && test $REPLACE_LOG2F = 0; then + AC_CACHE_CHECK([whether log2f works according to ISO C 99 with IEC 60559], + [gl_cv_func_log2f_ieee], + [ + save_LIBS="$LIBS" + LIBS="$LIBS $LOG2F_LIBM" + AC_RUN_IFELSE( + [AC_LANG_SOURCE([[ +#ifndef __NO_MATH_INLINES +# define __NO_MATH_INLINES 1 /* for glibc */ +#endif +#include +#ifndef log2f /* for Cygwin 1.7.x */ +extern +#ifdef __cplusplus +"C" +#endif +float log2f (float); +#endif +/* Compare two numbers with ==. + This is a separate function because IRIX 6.5 "cc -O" miscompiles an + 'x == x' test. */ +static int +numeric_equal (float x, float y) +{ + return x == y; +} +static float dummy (float x) { return 0; } +int main (int argc, char *argv[]) +{ + float (*my_log2f) (float) = argc ? log2f : dummy; + /* Test log2f(negative). + This test fails on NetBSD 5.1 and Solaris 11 2011-11. */ + float y = my_log2f (-1.0f); + if (numeric_equal (y, y)) + return 1; + return 0; +} + ]])], + [gl_cv_func_log2f_ieee=yes], + [gl_cv_func_log2f_ieee=no], + [gl_cv_func_log2f_ieee="guessing no"]) + LIBS="$save_LIBS" + ]) + case "$gl_cv_func_log2f_ieee" in + *yes) ;; + *) REPLACE_LOG2F=1 ;; + esac + fi + ]) else HAVE_LOG2F=0 HAVE_DECL_LOG2F=0 diff --git a/modules/log2f-ieee b/modules/log2f-ieee index 5849a918c..27ed2d0cf 100644 --- a/modules/log2f-ieee +++ b/modules/log2f-ieee @@ -2,12 +2,15 @@ Description: log2f() function according to ISO C 99 with IEC 60559. Files: +m4/log2f-ieee.m4 Depends-on: log2f fpieee +log2-ieee [test $HAVE_LOG2F = 0 || test $REPLACE_LOG2F = 1] configure.ac: +gl_FUNC_LOG2F_IEEE Makefile.am: -- 2.11.0