tests/test-snan-2.c

   1 /* Tests of signalling not-a-number.
   2    Copyright (C) 2023-2024 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2023.  */
  18
  19 #include <config.h>
  20
  21 /* Specification.  */
  22 #include "snan.h"
  23
  24 #include <stdio.h>
  25
  26 #include "fpe-trapping.h"
  27
  28 #if HAVE_FPE_TRAPPING
  29
  30 # include <fenv.h>
  31
  32 # include "macros.h"
  33
  34 float volatile resultf;
  35 double volatile resultd;
  36 long double volatile resultl;
  37
  38 int
  39 main (int argc, char *argv[])
  40 {
  41   /* Fetch the NaN values before we start watching out for FE_INVALID
  42      exceptions, because the division 0.0 / 0.0 itself also raises an
  43      FE_INVALID exception.
  44      The use of 'volatile' prevents the compiler from doing constant-folding
  45      optimizations on these values.  An alternative, for GCC only, would be
  46      the command-line option '-fsignaling-nans'.  */
  47   _GL_UNUSED float volatile nanf = SNaNf ();
  48   _GL_UNUSED double volatile nand = SNaNd ();
  49   _GL_UNUSED long double volatile nanl = SNaNl ();
  50
  51   /* Check that the values are really signalling.  */
  52
  53   /* Clear FE_INVALID exceptions from past operations.  */
  54   feclearexcept (FE_INVALID);
  55
  56   /* An FE_INVALID exception shall trigger a SIGFPE signal, which by default
  57      terminates the program.  */
  58   if (sigfpe_on_invalid () < 0)
  59     {
  60       fputs ("Skipping test: trapping floating-point exceptions are not supported on this machine.\n", stderr);
  61       return 77;
  62     }
  63
  64   if (argc > 1)
  65     switch (argv[1][0])
  66       {
  67       case 'f':
  68         /* This test does not work on 32-bit x86 processors, as well as
  69            on x86_64 processors with CC="gcc -mfpmath=387", because loading
  70            SNaNf() into a 387 FPU register already converted it to a quiet NaN.
  71            See <https://lists.gnu.org/archive/html/bug-gnulib/2023-10/msg00060.html>
  72            for details.  */
  73         #if !((defined __i386 || defined _M_IX86) \
  74               || ((defined __x86_64__ || defined _M_X64) && __FLT_EVAL_METHOD__ == 2))
  75         /* This test does not work on AIX 7.1 with the xlc compiler, even with
  76            the compiler options -qfloat=fenv -qfloat=nans -qfloat=spnans.  */
  77         #if !(defined _AIX && defined __xlC__)
  78         resultf = nanf + 42.0f;
  79         #else
  80         fputs ("Skipping test: known failure on this platform with this compiler\n", stderr);
  81         return 77;
  82         #endif
  83         #else
  84         fputs ("Skipping test: known failure on this platform\n", stderr);
  85         return 77;
  86         #endif
  87         break;
  88
  89       case 'd':
  90         /* This test does not work on 32-bit x86 processors, as well as
  91            on x86_64 processors with CC="gcc -mfpmath=387", because loading
  92            SNaNd() into a 387 FPU register already converted it to a quiet NaN.
  93            See <https://lists.gnu.org/archive/html/bug-gnulib/2023-10/msg00060.html>
  94            for details.  */
  95         #if !((defined __i386 || defined _M_IX86) \
  96               || ((defined __x86_64__ || defined _M_X64) && __FLT_EVAL_METHOD__ == 2))
  97         resultd = nand + 42.0;
  98         #else
  99         fputs ("Skipping test: known failure on this platform\n", stderr);
 100         return 77;
 101         #endif
 102         break;
 103
 104       case 'l':
 105         /* This test does not work on Linux/alpha with glibc 2.7.  But it
 106            works with glibc 2.36.  Cause unknown.
 107            This test does not work on Linux/loongarch64 with glibc 2.37.
 108            Cause unknown.
 109            This test does not work on eglibc 2.13/mips64
 110            (bug in libc function __addtf3).
 111            This test does not work on FreeBSD/arm64 and OpenBSD/mips64
 112            (bug in libc function __addtf3).
 113            This test does not work on FreeBSD/sparc64 and NetBSD/sparc64
 114            (bug in libc function _Qp_add).
 115            This test does not work on Cygwin 2.9.0/i386. Cause unknown.
 116            This test does not work on MSVC/i386, because of the general IA-32
 117            problem (see above) and 'long double' == 'double'.  */
 118         #if !((__GLIBC__ == 2 && __GLIBC_MINOR__ < 36 && defined __alpha__) \
 119               || (__GLIBC__ >= 2 && defined __loongarch__) \
 120               || (((__GLIBC__ == 2 && __GLIBC_MINOR__ < 19 && defined __mips64) \
 121                    || ((defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__) && (defined __aarch64__ || defined __mips64__ || defined __sparc__))) \
 122                   && !HAVE_SAME_LONG_DOUBLE_AS_DOUBLE) \
 123               || (defined __CYGWIN__ && defined __i386) \
 124               || (((defined __i386 || defined _M_IX86) \
 125                    || ((defined __x86_64__ || defined _M_X64) && __FLT_EVAL_METHOD__ == 2)) \
 126                   && HAVE_SAME_LONG_DOUBLE_AS_DOUBLE))
 127         resultl = nanl + 42.0L;
 128         #else
 129         fputs ("Skipping test: known failure on this platform\n", stderr);
 130         return 77;
 131         #endif
 132         break;
 133
 134       default:
 135         break;
 136       }
 137
 138   return test_exit_status;
 139 }
 140
 141 #else
 142
 143 /* No HAVE_FPE_TRAPPING available.
 144    We could use the various alternative approaches from
 145    libgfortran/config/fpu-*.h, but that's not worth it.  */
 146
 147 int
 148 main ()
 149 {
 150   fputs ("Skipping test: feenableexcept not available\n", stderr);
 151   return 77;
 152 }
 153
 154 #endif