diff options
Diffstat (limited to 'm4/frexp.m4')
-rw-r--r-- | m4/frexp.m4 | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/m4/frexp.m4 b/m4/frexp.m4 index 2e0fb3b..2eb98a1 100644 --- a/m4/frexp.m4 +++ b/m4/frexp.m4 @@ -1,5 +1,5 @@ -# frexp.m4 serial 10 -dnl Copyright (C) 2007-2011 Free Software Foundation, Inc. +# frexp.m4 serial 15 +dnl Copyright (C) 2007-2013 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. @@ -44,8 +44,6 @@ AC_DEFUN([gl_FUNC_FREXP], if test $gl_func_frexp = yes; then AC_DEFINE([HAVE_FREXP], [1], [Define if the frexp() function is available and works.]) - else - AC_LIBOBJ([frexp]) fi AC_SUBST([FREXP_LIBM]) ]) @@ -68,8 +66,6 @@ AC_DEFUN([gl_FUNC_FREXP_NO_LIBM], if test $gl_func_frexp_no_libm = yes; then AC_DEFINE([HAVE_FREXP_IN_LIBC], [1], [Define if the frexp() function is available in libc.]) - else - AC_LIBOBJ([frexp]) fi ]) @@ -92,11 +88,12 @@ AC_DEFUN([gl_CHECK_FREXP_NO_LIBM], dnl Test whether frexp() works also on denormalized numbers (this fails e.g. on dnl NetBSD 3.0), on infinite numbers (this fails e.g. on IRIX 6.5 and mingw), -dnl and on negative zero (this fails e.g. on NetBSD 4.99). +dnl and on negative zero (this fails e.g. on NetBSD 4.99 and mingw). AC_DEFUN([gl_FUNC_FREXP_WORKS], [ AC_REQUIRE([AC_PROG_CC]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CHECK_DECLS_ONCE([alarm]) AC_CACHE_CHECK([whether frexp works], [gl_cv_func_frexp_works], [ AC_RUN_IFELSE( @@ -104,10 +101,14 @@ AC_DEFUN([gl_FUNC_FREXP_WORKS], #include <float.h> #include <math.h> #include <string.h> +#if HAVE_DECL_ALARM +# include <signal.h> +# include <unistd.h> +#endif /* HP cc on HP-UX 10.20 has a bug with the constant expression -0.0. ICC 10.0 has a bug when optimizing the expression -zero. The expression -DBL_MIN * DBL_MIN does not work when cross-compiling - to PowerPC on MacOS X 10.5. */ + to PowerPC on Mac OS X 10.5. */ #if defined __hpux || defined __sgi || defined __ICC static double compute_minus_zero (void) @@ -124,6 +125,12 @@ int main() int i; volatile double x; double zero = 0.0; +#if HAVE_DECL_ALARM + /* NeXTstep 3.3 frexp() runs into an endless loop when called on an infinite + number. Let the test fail in this case. */ + signal (SIGALRM, SIG_DFL); + alarm (5); +#endif /* Test on denormalized numbers. */ for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5) ; @@ -137,7 +144,7 @@ int main() result |= 1; } /* Test on infinite numbers. */ - x = 1.0 / 0.0; + x = 1.0 / zero; { int exp; double y = frexp (x, &exp); |