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| author | Bruno Haible <bruno@clisp.org> | 2017-10-29 11:16:56 +0100 |
|---|---|---|
| committer | Bruno Haible <bruno@clisp.org> | 2017-10-29 21:27:50 +0100 |
| commit | 6065f427d616ccc578b38d92a5ef27bc4b6286ea (patch) | |
| tree | e4f59cbf1415f95ea68de8d9d789eb632e282176 /m4 | |
| parent | 5beeeb81c77cbcf72a7b9635fbad87e69432e6fd (diff) | |
| download | gnulib-6065f427d616ccc578b38d92a5ef27bc4b6286ea.tar.gz | |
expl: Ensure replacement on Haiku.
* m4/expl.m4 (gl_FUNC_EXPL): Test whether an expl() return value is
zero.
* doc/posix-functions/expl.texi: Mention the Haiku problem.
Diffstat (limited to 'm4')
| -rw-r--r-- | m4/expl.m4 | 50 |
1 files changed, 28 insertions, 22 deletions
diff --git a/m4/expl.m4 b/m4/expl.m4 index 2eddf0a19e..42db88b052 100644 --- a/m4/expl.m4 +++ b/m4/expl.m4 @@ -1,4 +1,4 @@ -# expl.m4 serial 10 +# expl.m4 serial 11 dnl Copyright (C) 2010-2017 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -54,31 +54,37 @@ AC_DEFUN([gl_FUNC_EXPL], EXPL_LIBM=-lm fi fi - dnl On OpenBSD5.4 the system's native expl() is buggy: + dnl On Haiku 2017 the system's native expl() is just a stub: it returns 0.0 + dnl and prints "__expl not implemented" for all arguments. + dnl On OpenBSD 5.4 the system's native expl() is buggy: dnl it returns 'nan' for small values. Test for this anomaly. if test $gl_cv_func_expl_no_libm = yes \ || test $gl_cv_func_expl_in_libm = yes; then AC_CACHE_CHECK([whether expl() breaks with small values], - [gl_cv_func_expl_buggy], - [ - save_LIBS="$LIBS" - LIBS="$EXPL_LIBM" - AC_RUN_IFELSE( - [AC_LANG_PROGRAM( - [[#include <math.h>]], - [[return isnan(expl(-1.0))|| - isnan(expl(-0.8))|| - isnan(expl(-0.4)); ]])], - [gl_cv_func_expl_buggy=no], [gl_cv_func_expl_buggy=yes], - [case $host_os in - openbsd*) gl_cv_func_expl_buggy="guessing yes" ;; - # Guess no on native Windows. - mingw*) gl_cv_func_expl_buggy="guessing no" ;; - *) gl_cv_func_expl_buggy="guessing no" ;; - esac - ]) - LIBS="$save_LIBS" - ]) + [gl_cv_func_expl_buggy], + [save_LIBS="$LIBS" + LIBS="$EXPL_LIBM" + AC_RUN_IFELSE( + [AC_LANG_PROGRAM( + [[#include <math.h>]], + [[volatile long double x1 = -1.0; + volatile long double x2 = -0.8; + volatile long double x3 = -0.4; + return expl(x1) == 0.0 || isnan(expl(x1)) + || isnan(expl(x2)) || isnan(expl(x3)); + ]]) + ], + [gl_cv_func_expl_buggy=no], [gl_cv_func_expl_buggy=yes], + [case $host_os in + haiku* | openbsd*) + gl_cv_func_expl_buggy="guessing yes" ;; + # Guess no on native Windows. + mingw*) gl_cv_func_expl_buggy="guessing no" ;; + *) gl_cv_func_expl_buggy="guessing no" ;; + esac + ]) + LIBS="$save_LIBS" + ]) case "$gl_cv_func_expl_buggy" in *yes) gl_cv_func_expl_in_libm=no |