math/test-misc.c

   1 /* Miscellaneous tests which don't fit anywhere else.
   2    Copyright (C) 2000-2013 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <fenv.h>
  20 #include <float.h>
  21 #include <ieee754.h>
  22 #include <math.h>
  23 #include <stdio.h>
  24 #include <string.h>
  25
  26
  27 int
  28 main (void)
  29 {
  30   int result = 0;
  31
  32 #ifndef NO_LONG_DOUBLE
  33   {
  34     long double x = 0x100000001ll + (long double) 0.5;
  35     long double q;
  36     long double r;
  37
  38     r = modfl (x, &q);
  39     if (q != (long double) 0x100000001ll || r != 0.5)
  40       {
  41         printf ("modfl (%Lg, ...) failed\n", x);
  42         result = 1;
  43       }
  44   }
  45
  46   {
  47     long double x;
  48     long double m;
  49     long double r;
  50     int e;
  51     int i;
  52
  53 # if LDBL_MANT_DIG == 64
  54     m = 0xf.fffffffffffffffp-4L;
  55 # elif LDBL_MANT_DIG == 106
  56     /* This has to match the mantissa of LDBL_MAX which actually does have a
  57        missing bit in the middle.  */
  58     m = 0x1.fffffffffffff7ffffffffffff8p-1L;
  59 # elif LDBL_MANT_DIG == 113
  60     m = 0x1.ffffffffffffffffffffffffffffp-1L;
  61 # else
  62 #  error "Please adjust"
  63 # endif
  64
  65     for (i = LDBL_MAX_EXP, x = LDBL_MAX; i >= LDBL_MIN_EXP; --i, x /= 2.0L)
  66       {
  67         printf ("2^%d: ", i);
  68
  69         r = frexpl (x, &e);
  70         if (r != m)
  71           {
  72             printf ("mantissa incorrect: %.20La\n", r);
  73             result = 1;
  74             continue;
  75           }
  76         if (e != i)
  77           {
  78             printf ("exponent wrong %d (%.20Lg)\n", e, x);
  79             result = 1;
  80             continue;
  81           }
  82         puts ("ok");
  83       }
  84
  85     for (i = LDBL_MIN_EXP, x = LDBL_MIN; i >= LDBL_MIN_EXP - LDBL_MANT_DIG + 1;
  86          --i, x /= 2.0L)
  87       {
  88         printf ("2^%d: ", i);
  89
  90         r = frexpl (x, &e);
  91         if (r != 0.5L)
  92           {
  93             printf ("mantissa incorrect: %.20La\n", r);
  94             result = 1;
  95             continue;
  96           }
  97         if (e != i)
  98           {
  99             printf ("exponent wrong %d (%.20Lg)\n", e, x);
 100             result = 1;
 101             continue;
 102           }
 103         puts ("ok");
 104       }
 105
 106   }
 107
 108 # if 0
 109   {
 110     int e;
 111     long double r = frexpl (LDBL_MIN * LDBL_EPSILON, &e);
 112
 113     if (r != 0.5)
 114       {
 115         printf ("frexpl (LDBL_MIN * LDBL_EPSILON, ...): mantissa wrong: %Lg\n",
 116                 r);
 117         result = 1;
 118       }
 119     else if (e != -16444)
 120       {
 121         printf ("frexpl (LDBL_MIN * LDBL_EPSILON, ...): exponent wrong: %d\n",
 122                 e);
 123         result = 1;
 124       }
 125   }
 126 # endif
 127 #endif
 128
 129   {
 130     double x = 0x100000001ll + (double) 0.5;
 131     double q;
 132     double r;
 133
 134     r = modf (x, &q);
 135     if (q != (double) 0x100000001ll || r != 0.5)
 136       {
 137         printf ("modf (%g, ...) failed\n", x);
 138         result = 1;
 139       }
 140   }
 141
 142   {
 143     union ieee754_float v1;
 144     union ieee754_float v2;
 145     float f;
 146
 147     v1.f = f = FLT_MIN;
 148     if (fpclassify (f) != FP_NORMAL)
 149       {
 150         printf ("fpclassify (FLT_MIN) failed: %d\n", fpclassify (f));
 151         result = 1;
 152       }
 153     f = nextafterf (f, FLT_MIN / 2.0f);
 154     if (fpclassify (f) != FP_SUBNORMAL)
 155       {
 156         printf ("fpclassify (FLT_MIN-epsilon) failed: %d\n", fpclassify (f));
 157         result = 1;
 158       }
 159     v2.f = f = nextafterf (f, FLT_MIN);
 160     if (fpclassify (f) != FP_NORMAL)
 161       {
 162         printf ("fpclassify (FLT_MIN-epsilon+epsilon) failed: %d\n",
 163                 fpclassify (f));
 164         result = 1;
 165       }
 166
 167     if (v1.ieee.mantissa != v2.ieee.mantissa)
 168       {
 169         printf ("FLT_MIN: mantissa differs: %8x vs %8x\n",
 170                 v1.ieee.mantissa, v2.ieee.mantissa);
 171         result = 1;
 172       }
 173     if (v1.ieee.exponent != v2.ieee.exponent)
 174       {
 175         printf ("FLT_MIN: exponent differs: %4x vs %4x\n",
 176                 v1.ieee.exponent, v2.ieee.exponent);
 177         result = 1;
 178       }
 179     if (v1.ieee.negative != v2.ieee.negative)
 180       {
 181         printf ("FLT_MIN: negative differs: %d vs %d\n",
 182                 v1.ieee.negative, v2.ieee.negative);
 183         result = 1;
 184       }
 185
 186     v1.f = f = -FLT_MIN;
 187     if (fpclassify (f) != FP_NORMAL)
 188       {
 189         printf ("fpclassify (-FLT_MIN) failed: %d\n", fpclassify (f));
 190         result = 1;
 191       }
 192     f = nextafterf (f, -FLT_MIN / 2.0f);
 193     if (fpclassify (f) != FP_SUBNORMAL)
 194       {
 195         printf ("fpclassify (-FLT_MIN-epsilon) failed: %d\n", fpclassify (f));
 196         result = 1;
 197       }
 198     v2.f = f = nextafterf (f, -FLT_MIN);
 199     if (fpclassify (f) != FP_NORMAL)
 200       {
 201         printf ("fpclassify (-FLT_MIN-epsilon+epsilon) failed: %d\n",
 202                 fpclassify (f));
 203         result = 1;
 204       }
 205
 206     if (v1.ieee.mantissa != v2.ieee.mantissa)
 207       {
 208         printf ("-FLT_MIN: mantissa differs: %8x vs %8x\n",
 209                 v1.ieee.mantissa, v2.ieee.mantissa);
 210         result = 1;
 211       }
 212     if (v1.ieee.exponent != v2.ieee.exponent)
 213       {
 214         printf ("-FLT_MIN: exponent differs: %4x vs %4x\n",
 215                 v1.ieee.exponent, v2.ieee.exponent);
 216         result = 1;
 217       }
 218     if (v1.ieee.negative != v2.ieee.negative)
 219       {
 220         printf ("-FLT_MIN: negative differs: %d vs %d\n",
 221                 v1.ieee.negative, v2.ieee.negative);
 222         result = 1;
 223       }
 224
 225     f = FLT_MAX;
 226     if (fpclassify (f) != FP_NORMAL)
 227       {
 228         printf ("fpclassify (FLT_MAX) failed: %d\n", fpclassify (f));
 229         result = 1;
 230       }
 231     f = nextafterf (f, INFINITY);
 232     if (fpclassify (f) != FP_INFINITE)
 233       {
 234         printf ("fpclassify (FLT_MAX+epsilon) failed: %d\n", fpclassify (f));
 235         result = 1;
 236       }
 237
 238     f = -FLT_MAX;
 239     if (fpclassify (f) != FP_NORMAL)
 240       {
 241         printf ("fpclassify (-FLT_MAX) failed: %d\n", fpclassify (f));
 242         result = 1;
 243       }
 244     f = nextafterf (f, -INFINITY);
 245     if (fpclassify (f) != FP_INFINITE)
 246       {
 247         printf ("fpclassify (-FLT_MAX-epsilon) failed: %d\n", fpclassify (f));
 248         result = 1;
 249       }
 250
 251     v1.f = f = 0.0625;
 252     f = nextafterf (f, 0.0);
 253     v2.f = f = nextafterf (f, 1.0);
 254
 255     if (v1.ieee.mantissa != v2.ieee.mantissa)
 256       {
 257         printf ("0.0625f down: mantissa differs: %8x vs %8x\n",
 258                 v1.ieee.mantissa, v2.ieee.mantissa);
 259         result = 1;
 260       }
 261     if (v1.ieee.exponent != v2.ieee.exponent)
 262       {
 263         printf ("0.0625f down: exponent differs: %4x vs %4x\n",
 264                 v1.ieee.exponent, v2.ieee.exponent);
 265         result = 1;
 266       }
 267     if (v1.ieee.negative != v2.ieee.negative)
 268       {
 269         printf ("0.0625f down: negative differs: %d vs %d\n",
 270                 v1.ieee.negative, v2.ieee.negative);
 271         result = 1;
 272       }
 273
 274     v1.f = f = 0.0625;
 275     f = nextafterf (f, 1.0);
 276     v2.f = f = nextafterf (f, 0.0);
 277
 278     if (v1.ieee.mantissa != v2.ieee.mantissa)
 279       {
 280         printf ("0.0625f up: mantissa differs: %8x vs %8x\n",
 281                 v1.ieee.mantissa, v2.ieee.mantissa);
 282         result = 1;
 283       }
 284     if (v1.ieee.exponent != v2.ieee.exponent)
 285       {
 286         printf ("0.0625f up: exponent differs: %4x vs %4x\n",
 287                 v1.ieee.exponent, v2.ieee.exponent);
 288         result = 1;
 289       }
 290     if (v1.ieee.negative != v2.ieee.negative)
 291       {
 292         printf ("0.0625f up: negative differs: %d vs %d\n",
 293                 v1.ieee.negative, v2.ieee.negative);
 294         result = 1;
 295       }
 296
 297     v1.f = f = -0.0625;
 298     f = nextafterf (f, 0.0);
 299     v2.f = f = nextafterf (f, -1.0);
 300
 301     if (v1.ieee.mantissa != v2.ieee.mantissa)
 302       {
 303         printf ("-0.0625f up: mantissa differs: %8x vs %8x\n",
 304                 v1.ieee.mantissa, v2.ieee.mantissa);
 305         result = 1;
 306       }
 307     if (v1.ieee.exponent != v2.ieee.exponent)
 308       {
 309         printf ("-0.0625f up: exponent differs: %4x vs %4x\n",
 310                 v1.ieee.exponent, v2.ieee.exponent);
 311         result = 1;
 312       }
 313     if (v1.ieee.negative != v2.ieee.negative)
 314       {
 315         printf ("-0.0625f up: negative differs: %d vs %d\n",
 316                 v1.ieee.negative, v2.ieee.negative);
 317         result = 1;
 318       }
 319
 320     v1.f = f = -0.0625;
 321     f = nextafterf (f, -1.0);
 322     v2.f = f = nextafterf (f, 0.0);
 323
 324     if (v1.ieee.mantissa != v2.ieee.mantissa)
 325       {
 326         printf ("-0.0625f down: mantissa differs: %8x vs %8x\n",
 327                 v1.ieee.mantissa, v2.ieee.mantissa);
 328         result = 1;
 329       }
 330     if (v1.ieee.exponent != v2.ieee.exponent)
 331       {
 332         printf ("-0.0625f down: exponent differs: %4x vs %4x\n",
 333                 v1.ieee.exponent, v2.ieee.exponent);
 334         result = 1;
 335       }
 336     if (v1.ieee.negative != v2.ieee.negative)
 337       {
 338         printf ("-0.0625f down: negative differs: %d vs %d\n",
 339                 v1.ieee.negative, v2.ieee.negative);
 340         result = 1;
 341       }
 342
 343     v1.f = f = 0.0f;
 344     f = nextafterf (f, 1.0);
 345     v2.f = nextafterf (f, -1.0);
 346
 347     if (v1.ieee.mantissa != v2.ieee.mantissa)
 348       {
 349         printf ("0.0f up: mantissa differs: %8x vs %8x\n",
 350                 v1.ieee.mantissa, v2.ieee.mantissa);
 351         result = 1;
 352       }
 353     if (v1.ieee.exponent != v2.ieee.exponent)
 354       {
 355         printf ("0.0f up: exponent differs: %4x vs %4x\n",
 356                 v1.ieee.exponent, v2.ieee.exponent);
 357         result = 1;
 358       }
 359     if (0 != v2.ieee.negative)
 360       {
 361         printf ("0.0f up: negative differs: 0 vs %d\n",
 362                 v2.ieee.negative);
 363         result = 1;
 364       }
 365
 366     v1.f = f = 0.0f;
 367     f = nextafterf (f, -1.0);
 368     v2.f = nextafterf (f, 1.0);
 369
 370     if (v1.ieee.mantissa != v2.ieee.mantissa)
 371       {
 372         printf ("0.0f down: mantissa differs: %8x vs %8x\n",
 373                 v1.ieee.mantissa, v2.ieee.mantissa);
 374         result = 1;
 375       }
 376     if (v1.ieee.exponent != v2.ieee.exponent)
 377       {
 378         printf ("0.0f down: exponent differs: %4x vs %4x\n",
 379                 v1.ieee.exponent, v2.ieee.exponent);
 380         result = 1;
 381       }
 382     if (1 != v2.ieee.negative)
 383       {
 384         printf ("0.0f down: negative differs: 1 vs %d\n",
 385                 v2.ieee.negative);
 386         result = 1;
 387       }
 388
 389     if (nextafterf (0.0f, INFINITY) != nextafterf (0.0f, 1.0f)
 390         || nextafterf (-0.0f, INFINITY) != nextafterf (-0.0f, 1.0f)
 391         || nextafterf (0.0f, -INFINITY) != nextafterf (0.0f, -1.0f)
 392         || nextafterf (-0.0f, -INFINITY) != nextafterf (-0.0f, -1.0f))
 393       {
 394         printf ("nextafterf (+-0, +-Inf) != nextafterf (+-0, +-1)\n");
 395         result = 1;
 396       }
 397
 398     if (nexttowardf (0.0f, INFINITY) != nexttowardf (0.0f, 1.0f)
 399         || nexttowardf (-0.0f, INFINITY) != nexttowardf (-0.0f, 1.0f)
 400         || nexttowardf (0.0f, -INFINITY) != nexttowardf (0.0f, -1.0f)
 401         || nexttowardf (-0.0f, -INFINITY) != nexttowardf (-0.0f, -1.0f))
 402       {
 403         printf ("nexttowardf (+-0, +-Inf) != nexttowardf (+-0, +-1)\n");
 404         result = 1;
 405       }
 406   }
 407
 408   {
 409     union ieee754_double v1;
 410     union ieee754_double v2;
 411     double d;
 412
 413     v1.d = d = DBL_MIN;
 414     if (fpclassify (d) != FP_NORMAL)
 415       {
 416         printf ("fpclassify (DBL_MIN) failed: %d\n", fpclassify (d));
 417         result = 1;
 418       }
 419     d = nextafter (d, DBL_MIN / 2.0);
 420     if (fpclassify (d) != FP_SUBNORMAL)
 421       {
 422         printf ("fpclassify (DBL_MIN-epsilon) failed: %d\n", fpclassify (d));
 423         result = 1;
 424       }
 425     v2.d = d = nextafter (d, DBL_MIN);
 426     if (fpclassify (d) != FP_NORMAL)
 427       {
 428         printf ("fpclassify (DBL_MIN-epsilon+epsilon) failed: %d\n",
 429                 fpclassify (d));
 430         result = 1;
 431       }
 432
 433     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 434       {
 435         printf ("DBL_MIN: mantissa0 differs: %8x vs %8x\n",
 436                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 437         result = 1;
 438       }
 439     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 440       {
 441         printf ("DBL_MIN: mantissa1 differs: %8x vs %8x\n",
 442                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 443         result = 1;
 444       }
 445     if (v1.ieee.exponent != v2.ieee.exponent)
 446       {
 447         printf ("DBL_MIN: exponent differs: %4x vs %4x\n",
 448                 v1.ieee.exponent, v2.ieee.exponent);
 449         result = 1;
 450       }
 451     if (v1.ieee.negative != v2.ieee.negative)
 452       {
 453         printf ("DBL_MIN: negative differs: %d vs %d\n",
 454                 v1.ieee.negative, v2.ieee.negative);
 455         result = 1;
 456       }
 457
 458     v1.d = d = -DBL_MIN;
 459     if (fpclassify (d) != FP_NORMAL)
 460       {
 461         printf ("fpclassify (-DBL_MIN) failed: %d\n", fpclassify (d));
 462         result = 1;
 463       }
 464     d = nextafter (d, -DBL_MIN / 2.0);
 465     if (fpclassify (d) != FP_SUBNORMAL)
 466       {
 467         printf ("fpclassify (-DBL_MIN-epsilon) failed: %d\n", fpclassify (d));
 468         result = 1;
 469       }
 470     v2.d = d = nextafter (d, -DBL_MIN);
 471     if (fpclassify (d) != FP_NORMAL)
 472       {
 473         printf ("fpclassify (-DBL_MIN-epsilon+epsilon) failed: %d\n",
 474                 fpclassify (d));
 475         result = 1;
 476       }
 477
 478     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 479       {
 480         printf ("-DBL_MIN: mantissa0 differs: %8x vs %8x\n",
 481                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 482         result = 1;
 483       }
 484     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 485       {
 486         printf ("-DBL_MIN: mantissa1 differs: %8x vs %8x\n",
 487                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 488         result = 1;
 489       }
 490     if (v1.ieee.exponent != v2.ieee.exponent)
 491       {
 492         printf ("-DBL_MIN: exponent differs: %4x vs %4x\n",
 493                 v1.ieee.exponent, v2.ieee.exponent);
 494         result = 1;
 495       }
 496     if (v1.ieee.negative != v2.ieee.negative)
 497       {
 498         printf ("-DBL_MIN: negative differs: %d vs %d\n",
 499                 v1.ieee.negative, v2.ieee.negative);
 500         result = 1;
 501       }
 502
 503     d = DBL_MAX;
 504     if (fpclassify (d) != FP_NORMAL)
 505       {
 506         printf ("fpclassify (DBL_MAX) failed: %d\n", fpclassify (d));
 507         result = 1;
 508       }
 509     d = nextafter (d, INFINITY);
 510     if (fpclassify (d) != FP_INFINITE)
 511       {
 512         printf ("fpclassify (DBL_MAX+epsilon) failed: %d\n", fpclassify (d));
 513         result = 1;
 514       }
 515
 516     d = -DBL_MAX;
 517     if (fpclassify (d) != FP_NORMAL)
 518       {
 519         printf ("fpclassify (-DBL_MAX) failed: %d\n", fpclassify (d));
 520         result = 1;
 521       }
 522     d = nextafter (d, -INFINITY);
 523     if (fpclassify (d) != FP_INFINITE)
 524       {
 525         printf ("fpclassify (-DBL_MAX-epsilon) failed: %d\n", fpclassify (d));
 526         result = 1;
 527       }
 528
 529     v1.d = d = 0.0625;
 530     d = nextafter (d, 0.0);
 531     v2.d = d = nextafter (d, 1.0);
 532
 533     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 534       {
 535         printf ("0.0625 down: mantissa0 differs: %8x vs %8x\n",
 536                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 537         result = 1;
 538       }
 539     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 540       {
 541         printf ("0.0625 down: mantissa1 differs: %8x vs %8x\n",
 542                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 543         result = 1;
 544       }
 545     if (v1.ieee.exponent != v2.ieee.exponent)
 546       {
 547         printf ("0.0625 down: exponent differs: %4x vs %4x\n",
 548                 v1.ieee.exponent, v2.ieee.exponent);
 549         result = 1;
 550       }
 551     if (v1.ieee.negative != v2.ieee.negative)
 552       {
 553         printf ("0.0625 down: negative differs: %d vs %d\n",
 554                 v1.ieee.negative, v2.ieee.negative);
 555         result = 1;
 556       }
 557
 558     v1.d = d = 0.0625;
 559     d = nextafter (d, 1.0);
 560     v2.d = d = nextafter (d, 0.0);
 561
 562     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 563       {
 564         printf ("0.0625 up: mantissa0 differs: %8x vs %8x\n",
 565                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 566         result = 1;
 567       }
 568     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 569       {
 570         printf ("0.0625 up: mantissa1 differs: %8x vs %8x\n",
 571                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 572         result = 1;
 573       }
 574     if (v1.ieee.exponent != v2.ieee.exponent)
 575       {
 576         printf ("0.0625 up: exponent differs: %4x vs %4x\n",
 577                 v1.ieee.exponent, v2.ieee.exponent);
 578         result = 1;
 579       }
 580     if (v1.ieee.negative != v2.ieee.negative)
 581       {
 582         printf ("0.0625 up: negative differs: %d vs %d\n",
 583                 v1.ieee.negative, v2.ieee.negative);
 584         result = 1;
 585       }
 586
 587     v1.d = d = -0.0625;
 588     d = nextafter (d, 0.0);
 589     v2.d = d = nextafter (d, -1.0);
 590
 591     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 592       {
 593         printf ("-0.0625 up: mantissa0 differs: %8x vs %8x\n",
 594                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 595         result = 1;
 596       }
 597     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 598       {
 599         printf ("-0.0625 up: mantissa1 differs: %8x vs %8x\n",
 600                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 601         result = 1;
 602       }
 603     if (v1.ieee.exponent != v2.ieee.exponent)
 604       {
 605         printf ("-0.0625 up: exponent differs: %4x vs %4x\n",
 606                 v1.ieee.exponent, v2.ieee.exponent);
 607         result = 1;
 608       }
 609     if (v1.ieee.negative != v2.ieee.negative)
 610       {
 611         printf ("-0.0625 up: negative differs: %d vs %d\n",
 612                 v1.ieee.negative, v2.ieee.negative);
 613         result = 1;
 614       }
 615
 616     v1.d = d = -0.0625;
 617     d = nextafter (d, -1.0);
 618     v2.d = d = nextafter (d, 0.0);
 619
 620     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 621       {
 622         printf ("-0.0625 down: mantissa0 differs: %8x vs %8x\n",
 623                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 624         result = 1;
 625       }
 626     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 627       {
 628         printf ("-0.0625 down: mantissa1 differs: %8x vs %8x\n",
 629                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 630         result = 1;
 631       }
 632     if (v1.ieee.exponent != v2.ieee.exponent)
 633       {
 634         printf ("-0.0625 down: exponent differs: %4x vs %4x\n",
 635                 v1.ieee.exponent, v2.ieee.exponent);
 636         result = 1;
 637       }
 638     if (v1.ieee.negative != v2.ieee.negative)
 639       {
 640         printf ("-0.0625 down: negative differs: %d vs %d\n",
 641                 v1.ieee.negative, v2.ieee.negative);
 642         result = 1;
 643       }
 644
 645     v1.d = d = 0.0;
 646     d = nextafter (d, 1.0);
 647     v2.d = nextafter (d, -1.0);
 648
 649     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 650       {
 651         printf ("0.0 up: mantissa0 differs: %8x vs %8x\n",
 652                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 653         result = 1;
 654       }
 655     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 656       {
 657         printf ("0.0 up: mantissa1 differs: %8x vs %8x\n",
 658                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 659         result = 1;
 660       }
 661     if (v1.ieee.exponent != v2.ieee.exponent)
 662       {
 663         printf ("0.0 up: exponent differs: %4x vs %4x\n",
 664                 v1.ieee.exponent, v2.ieee.exponent);
 665         result = 1;
 666       }
 667     if (0 != v2.ieee.negative)
 668       {
 669         printf ("0.0 up: negative differs: 0 vs %d\n",
 670                 v2.ieee.negative);
 671         result = 1;
 672       }
 673
 674     v1.d = d = 0.0;
 675     d = nextafter (d, -1.0);
 676     v2.d = nextafter (d, 1.0);
 677
 678     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 679       {
 680         printf ("0.0 down: mantissa0 differs: %8x vs %8x\n",
 681                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 682         result = 1;
 683       }
 684     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 685       {
 686         printf ("0.0 down: mantissa1 differs: %8x vs %8x\n",
 687                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 688         result = 1;
 689       }
 690     if (v1.ieee.exponent != v2.ieee.exponent)
 691       {
 692         printf ("0.0 down: exponent differs: %4x vs %4x\n",
 693                 v1.ieee.exponent, v2.ieee.exponent);
 694         result = 1;
 695       }
 696     if (1 != v2.ieee.negative)
 697       {
 698         printf ("0.0 down: negative differs: 1 vs %d\n",
 699                 v2.ieee.negative);
 700         result = 1;
 701       }
 702
 703     if (nextafter (0.0, INFINITY) != nextafter (0.0, 1.0)
 704         || nextafter (-0.0, INFINITY) != nextafter (-0.0, 1.0)
 705         || nextafter (0.0, -INFINITY) != nextafter (0.0, -1.0)
 706         || nextafter (-0.0, -INFINITY) != nextafter (-0.0, -1.0))
 707       {
 708         printf ("nextafter (+-0, +-Inf) != nextafter (+-0, +-1)\n");
 709         result = 1;
 710       }
 711
 712     if (nexttoward (0.0, INFINITY) != nexttoward (0.0, 1.0)
 713         || nexttoward (-0.0, INFINITY) != nexttoward (-0.0, 1.0)
 714         || nexttoward (0.0, -INFINITY) != nexttoward (0.0, -1.0)
 715         || nexttoward (-0.0, -INFINITY) != nexttoward (-0.0, -1.0))
 716       {
 717         printf ("nexttoward (+-0, +-Inf) != nexttoward (+-0, +-1)\n");
 718         result = 1;
 719       }
 720   }
 721
 722 #ifndef NO_LONG_DOUBLE
 723   {
 724     union ieee854_long_double v1;
 725     union ieee854_long_double v2;
 726     long double ld;
 727
 728     v1.d = ld = LDBL_MIN;
 729     if (fpclassify (ld) != FP_NORMAL)
 730       {
 731         printf ("fpclassify (LDBL_MIN) failed: %d\n", fpclassify (ld));
 732         result = 1;
 733       }
 734     ld = nextafterl (ld, LDBL_MIN / 2.0);
 735     if (fpclassify (ld) != FP_SUBNORMAL)
 736       {
 737         printf ("fpclassify (LDBL_MIN-epsilon) failed: %d (%La)\n",
 738                 fpclassify (ld), ld);
 739         result = 1;
 740       }
 741     v2.d = ld = nextafterl (ld, LDBL_MIN);
 742     if (fpclassify (ld) != FP_NORMAL)
 743       {
 744         printf ("fpclassify (LDBL_MIN-epsilon+epsilon) failed: %d (%La)\n",
 745                 fpclassify (ld), ld);
 746         result = 1;
 747       }
 748
 749     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 750       {
 751         printf ("LDBL_MIN: mantissa0 differs: %8x vs %8x\n",
 752                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 753         result = 1;
 754       }
 755     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 756       {
 757         printf ("LDBL_MIN: mantissa1 differs: %8x vs %8x\n",
 758                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 759         result = 1;
 760       }
 761     if (v1.ieee.exponent != v2.ieee.exponent)
 762       {
 763         printf ("LDBL_MIN: exponent differs: %4x vs %4x\n",
 764                 v1.ieee.exponent, v2.ieee.exponent);
 765         result = 1;
 766       }
 767     if (v1.ieee.negative != v2.ieee.negative)
 768       {
 769         printf ("LDBL_MIN: negative differs: %d vs %d\n",
 770                 v1.ieee.negative, v2.ieee.negative);
 771         result = 1;
 772       }
 773
 774     v1.d = ld = -LDBL_MIN;
 775     if (fpclassify (ld) != FP_NORMAL)
 776       {
 777         printf ("fpclassify (-LDBL_MIN) failed: %d\n", fpclassify (ld));
 778         result = 1;
 779       }
 780     ld = nextafterl (ld, -LDBL_MIN / 2.0);
 781     if (fpclassify (ld) != FP_SUBNORMAL)
 782       {
 783         printf ("fpclassify (-LDBL_MIN-epsilon) failed: %d (%La)\n",
 784                 fpclassify (ld), ld);
 785         result = 1;
 786       }
 787     v2.d = ld = nextafterl (ld, -LDBL_MIN);
 788     if (fpclassify (ld) != FP_NORMAL)
 789       {
 790         printf ("fpclassify (-LDBL_MIN-epsilon+epsilon) failed: %d (%La)\n",
 791                 fpclassify (ld), ld);
 792         result = 1;
 793       }
 794
 795     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 796       {
 797         printf ("-LDBL_MIN: mantissa0 differs: %8x vs %8x\n",
 798                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 799         result = 1;
 800       }
 801     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 802       {
 803         printf ("-LDBL_MIN: mantissa1 differs: %8x vs %8x\n",
 804                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 805         result = 1;
 806       }
 807     if (v1.ieee.exponent != v2.ieee.exponent)
 808       {
 809         printf ("-LDBL_MIN: exponent differs: %4x vs %4x\n",
 810                 v1.ieee.exponent, v2.ieee.exponent);
 811         result = 1;
 812       }
 813     if (v1.ieee.negative != v2.ieee.negative)
 814       {
 815         printf ("-LDBL_MIN: negative differs: %d vs %d\n",
 816                 v1.ieee.negative, v2.ieee.negative);
 817         result = 1;
 818       }
 819
 820     ld = LDBL_MAX;
 821     if (fpclassify (ld) != FP_NORMAL)
 822       {
 823         printf ("fpclassify (LDBL_MAX) failed: %d\n", fpclassify (ld));
 824         result = 1;
 825       }
 826     ld = nextafterl (ld, INFINITY);
 827     if (fpclassify (ld) != FP_INFINITE)
 828       {
 829         printf ("fpclassify (LDBL_MAX+epsilon) failed: %d\n", fpclassify (ld));
 830         result = 1;
 831       }
 832
 833     ld = -LDBL_MAX;
 834     if (fpclassify (ld) != FP_NORMAL)
 835       {
 836         printf ("fpclassify (-LDBL_MAX) failed: %d\n", fpclassify (ld));
 837         result = 1;
 838       }
 839     ld = nextafterl (ld, -INFINITY);
 840     if (fpclassify (ld) != FP_INFINITE)
 841       {
 842         printf ("fpclassify (-LDBL_MAX-epsilon) failed: %d\n",
 843                 fpclassify (ld));
 844         result = 1;
 845       }
 846
 847     v1.d = ld = 0.0625;
 848     ld = nextafterl (ld, 0.0);
 849     v2.d = ld = nextafterl (ld, 1.0);
 850
 851     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 852       {
 853         printf ("0.0625L down: mantissa0 differs: %8x vs %8x\n",
 854                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 855         result = 1;
 856       }
 857     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 858       {
 859         printf ("0.0625L down: mantissa1 differs: %8x vs %8x\n",
 860                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 861         result = 1;
 862       }
 863     if (v1.ieee.exponent != v2.ieee.exponent)
 864       {
 865         printf ("0.0625L down: exponent differs: %4x vs %4x\n",
 866                 v1.ieee.exponent, v2.ieee.exponent);
 867         result = 1;
 868       }
 869     if (v1.ieee.negative != v2.ieee.negative)
 870       {
 871         printf ("0.0625L down: negative differs: %d vs %d\n",
 872                 v1.ieee.negative, v2.ieee.negative);
 873         result = 1;
 874       }
 875
 876     v1.d = ld = 0.0625;
 877     ld = nextafterl (ld, 1.0);
 878     v2.d = ld = nextafterl (ld, 0.0);
 879
 880     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 881       {
 882         printf ("0.0625L up: mantissa0 differs: %8x vs %8x\n",
 883                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 884         result = 1;
 885       }
 886     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 887       {
 888         printf ("0.0625L up: mantissa1 differs: %8x vs %8x\n",
 889                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 890         result = 1;
 891       }
 892     if (v1.ieee.exponent != v2.ieee.exponent)
 893       {
 894         printf ("0.0625L up: exponent differs: %4x vs %4x\n",
 895                 v1.ieee.exponent, v2.ieee.exponent);
 896         result = 1;
 897       }
 898     if (v1.ieee.negative != v2.ieee.negative)
 899       {
 900         printf ("0.0625L up: negative differs: %d vs %d\n",
 901                 v1.ieee.negative, v2.ieee.negative);
 902         result = 1;
 903       }
 904
 905     v1.d = ld = -0.0625;
 906     ld = nextafterl (ld, 0.0);
 907     v2.d = ld = nextafterl (ld, -1.0);
 908
 909     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 910       {
 911         printf ("-0.0625L up: mantissa0 differs: %8x vs %8x\n",
 912                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 913         result = 1;
 914       }
 915     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 916       {
 917         printf ("-0.0625L up: mantissa1 differs: %8x vs %8x\n",
 918                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 919         result = 1;
 920       }
 921     if (v1.ieee.exponent != v2.ieee.exponent)
 922       {
 923         printf ("-0.0625L up: exponent differs: %4x vs %4x\n",
 924                 v1.ieee.exponent, v2.ieee.exponent);
 925         result = 1;
 926       }
 927     if (v1.ieee.negative != v2.ieee.negative)
 928       {
 929         printf ("-0.0625L up: negative differs: %d vs %d\n",
 930                 v1.ieee.negative, v2.ieee.negative);
 931         result = 1;
 932       }
 933
 934     v1.d = ld = -0.0625;
 935     ld = nextafterl (ld, -1.0);
 936     v2.d = ld = nextafterl (ld, 0.0);
 937
 938     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 939       {
 940         printf ("-0.0625L down: mantissa0 differs: %8x vs %8x\n",
 941                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 942         result = 1;
 943       }
 944     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 945       {
 946         printf ("-0.0625L down: mantissa1 differs: %8x vs %8x\n",
 947                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 948         result = 1;
 949       }
 950     if (v1.ieee.exponent != v2.ieee.exponent)
 951       {
 952         printf ("-0.0625L down: exponent differs: %4x vs %4x\n",
 953                 v1.ieee.exponent, v2.ieee.exponent);
 954         result = 1;
 955       }
 956     if (v1.ieee.negative != v2.ieee.negative)
 957       {
 958         printf ("-0.0625L down: negative differs: %d vs %d\n",
 959                 v1.ieee.negative, v2.ieee.negative);
 960         result = 1;
 961       }
 962
 963     v1.d = ld = 0.0;
 964     ld = nextafterl (ld, 1.0);
 965     v2.d = nextafterl (ld, -1.0);
 966
 967     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 968       {
 969         printf ("0.0L up: mantissa0 differs: %8x vs %8x\n",
 970                 v1.ieee.mantissa0, v2.ieee.mantissa0);
 971         result = 1;
 972       }
 973     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
 974       {
 975         printf ("0.0L up: mantissa1 differs: %8x vs %8x\n",
 976                 v1.ieee.mantissa1, v2.ieee.mantissa1);
 977         result = 1;
 978       }
 979     if (v1.ieee.exponent != v2.ieee.exponent)
 980       {
 981         printf ("0.0L up: exponent differs: %4x vs %4x\n",
 982                 v1.ieee.exponent, v2.ieee.exponent);
 983         result = 1;
 984       }
 985     if (0 != v2.ieee.negative)
 986       {
 987         printf ("0.0L up: negative differs: 0 vs %d\n",
 988                 v2.ieee.negative);
 989         result = 1;
 990       }
 991
 992     v1.d = ld = 0.0;
 993     ld = nextafterl (ld, -1.0);
 994     v2.d = nextafterl (ld, 1.0);
 995
 996     if (v1.ieee.mantissa0 != v2.ieee.mantissa0)
 997       {
 998         printf ("0.0L down: mantissa0 differs: %8x vs %8x\n",
 999                 v1.ieee.mantissa0, v2.ieee.mantissa0);
1000         result = 1;
1001       }
1002     if (v1.ieee.mantissa1 != v2.ieee.mantissa1)
1003       {
1004         printf ("0.0L down: mantissa1 differs: %8x vs %8x\n",
1005                 v1.ieee.mantissa1, v2.ieee.mantissa1);
1006         result = 1;
1007       }
1008     if (v1.ieee.exponent != v2.ieee.exponent)
1009       {
1010         printf ("0.0L down: exponent differs: %4x vs %4x\n",
1011                 v1.ieee.exponent, v2.ieee.exponent);
1012         result = 1;
1013       }
1014     if (1 != v2.ieee.negative)
1015       {
1016         printf ("0.0L down: negative differs: 1 vs %d\n",
1017                 v2.ieee.negative);
1018         result = 1;
1019       }
1020
1021     if (nextafterl (0.0, INFINITY) != nextafterl (0.0, 1.0)
1022         || nextafterl (-0.0, INFINITY) != nextafterl (-0.0, 1.0)
1023         || nextafterl (0.0, -INFINITY) != nextafterl (0.0, -1.0)
1024         || nextafterl (-0.0, -INFINITY) != nextafterl (-0.0, -1.0))
1025       {
1026         printf ("nextafterl (+-0, +-Inf) != nextafterl (+-0, +-1)\n");
1027         result = 1;
1028       }
1029
1030     if (nexttowardl (0.0L, INFINITY) != nexttowardl (0.0L, 1.0L)
1031         || nexttowardl (-0.0L, INFINITY) != nexttowardl (-0.0L, 1.0L)
1032         || nexttowardl (0.0L, -INFINITY) != nexttowardl (0.0L, -1.0L)
1033         || nexttowardl (-0.0L, -INFINITY) != nexttowardl (-0.0L, -1.0L))
1034       {
1035         printf ("nexttowardl (+-0, +-Inf) != nexttowardl (+-0, +-1)\n");
1036         result = 1;
1037       }
1038   }
1039 #endif
1040
1041   if (! isnormal (FLT_MIN))
1042     {
1043       puts ("isnormal (FLT_MIN) failed");
1044       result = 1;
1045     }
1046   if (! isnormal (DBL_MIN))
1047     {
1048       puts ("isnormal (DBL_MIN) failed");
1049       result = 1;
1050     }
1051 #ifndef NO_LONG_DOUBLE
1052   if (! isnormal (LDBL_MIN))
1053     {
1054       puts ("isnormal (LDBL_MIN) failed");
1055       result = 1;
1056     }
1057 #endif
1058
1059 #if defined (__i386__) || defined (__x86_64__)
1060   /* This is a test for the strange long doubles in x86 FPUs.  */
1061   {
1062     union
1063     {
1064       char b[10];
1065       long double d;
1066     } u =
1067       { .b = { 0, 0, 0, 0, 0, 0, 0, 0x80, 0, 0 } };
1068
1069     if (fpclassify (u.d) != FP_NORMAL)
1070       {
1071         printf ("fpclassify (0x00008000000000000000) failed: %d (%Lg)\n",
1072                 fpclassify (u.d), u.d);
1073         result = 1;
1074       }
1075   }
1076
1077   /* Special qNaNs in x86 long double.  Test for scalbl.  */
1078   {
1079     union
1080     {
1081       char b[10];
1082       long double d;
1083     } u =
1084       { .b = { 0, 1, 0, 0, 0, 0, 0, 0xc0, 0xff, 0x7f } };
1085     long double r;
1086
1087     r = scalbl (u.d, 0.0);
1088     if (!isnan (r))
1089       {
1090         puts ("scalbl (qNaN, 0) does not return NaN");
1091         result = 1;
1092       }
1093     else if (memcmp (&r, &u.d, sizeof (double)) != 0)
1094       {
1095         puts ("scalbl (qNaN, 0) does not return the same NaN");
1096         result = 1;
1097       }
1098   }
1099 #endif
1100
1101 #ifndef NO_LONG_DOUBLE
1102   {
1103     long double r;
1104
1105     feclearexcept (FE_ALL_EXCEPT);
1106     r = scalbl (LDBL_MIN, 2147483647);
1107     if (! isinf (r))
1108       {
1109         puts ("scalbl (LDBL_MIN, 2147483647) does not return Inf");
1110         result = 1;
1111       }
1112     else if (signbit (r) != 0)
1113       {
1114         puts ("scalbl (LDBL_MIN, 2147483647) returns -Inf");
1115         result = 1;
1116       }
1117     else if (fetestexcept (FE_UNDERFLOW))
1118       {
1119         puts ("scalbl (LDBL_MIN, 2147483647) raises underflow exception");
1120         result = 1;
1121       }
1122
1123     feclearexcept (FE_ALL_EXCEPT);
1124     r = scalbl (LDBL_MAX, -2147483647);
1125     if (r != 0.0)
1126       {
1127         puts ("scalbl (LDBL_MAX, -2147483647) does not return 0");
1128         result = 1;
1129       }
1130     else if (signbit (r) != 0)
1131       {
1132         puts ("scalbl (LDBL_MAX, -2147483647) returns -Inf");
1133         result = 1;
1134       }
1135     else if (fetestexcept (FE_OVERFLOW))
1136       {
1137         puts ("scalbl (LDBL_MAX, -2147483647) raises overflow exception");
1138         result = 1;
1139       }
1140   }
1141 #endif
1142
1143   /* The tests here are very similar to tests earlier in this file,
1144      the important difference is just that there are no intervening
1145      union variables that cause some GCC versions to hide possible
1146      bugs in nextafter* implementation.  */
1147   if (nextafterf (nextafterf (FLT_MIN, FLT_MIN / 2.0), FLT_MIN) != FLT_MIN)
1148     {
1149       puts ("nextafterf FLT_MIN test failed");
1150       result = 1;
1151     }
1152   if (nextafterf (nextafterf (-FLT_MIN, -FLT_MIN / 2.0), -FLT_MIN)
1153       != -FLT_MIN)
1154     {
1155       puts ("nextafterf -FLT_MIN test failed");
1156       result = 1;
1157     }
1158   if (nextafter (nextafter (DBL_MIN, DBL_MIN / 2.0), DBL_MIN) != DBL_MIN)
1159     {
1160       puts ("nextafter DBL_MIN test failed");
1161       result = 1;
1162     }
1163   if (nextafter (nextafter (-DBL_MIN, -DBL_MIN / 2.0), -DBL_MIN) != -DBL_MIN)
1164     {
1165       puts ("nextafter -DBL_MIN test failed");
1166       result = 1;
1167     }
1168 #ifndef NO_LONG_DOUBLE
1169   if (nextafterl (nextafterl (LDBL_MIN, LDBL_MIN / 2.0), LDBL_MIN)
1170       != LDBL_MIN)
1171     {
1172       puts ("nextafterl LDBL_MIN test failed");
1173       result = 1;
1174     }
1175   if (nextafterl (nextafterl (-LDBL_MIN, -LDBL_MIN / 2.0), -LDBL_MIN)
1176       != -LDBL_MIN)
1177     {
1178       puts ("nextafterl -LDBL_MIN test failed");
1179       result = 1;
1180     }
1181 #endif
1182
1183   volatile float f1 = FLT_MAX;
1184   volatile float f2 = FLT_MAX / 2;
1185   (void) &f1;
1186   (void) &f2;
1187   feclearexcept (FE_ALL_EXCEPT);
1188   f2 += f1;
1189 #if defined(FE_OVERFLOW) && defined(FE_INEXACT)
1190   int fe = fetestexcept (FE_ALL_EXCEPT);
1191   if (fe != (FE_OVERFLOW | FE_INEXACT))
1192     {
1193       printf ("float overflow test failed: %x\n", fe);
1194       result = 1;
1195     }
1196 #endif
1197
1198   volatile double d1 = DBL_MAX;
1199   volatile double d2 = DBL_MAX / 2;
1200   (void) &d1;
1201   (void) &d2;
1202   feclearexcept (FE_ALL_EXCEPT);
1203   d2 += d1;
1204 #if defined(FE_OVERFLOW) && defined(FE_INEXACT)
1205   fe = fetestexcept (FE_ALL_EXCEPT);
1206   if (fe != (FE_OVERFLOW | FE_INEXACT))
1207     {
1208       printf ("double overflow test failed: %x\n", fe);
1209       result = 1;
1210     }
1211 #endif
1212
1213 #ifndef NO_LONG_DOUBLE
1214   volatile long double ld1 = LDBL_MAX;
1215   volatile long double ld2 = LDBL_MAX / 2;
1216   (void) &ld1;
1217   (void) &ld2;
1218   feclearexcept (FE_ALL_EXCEPT);
1219   ld2 += ld1;
1220 # if defined(FE_OVERFLOW) && defined(FE_INEXACT)
1221   fe = fetestexcept (FE_ALL_EXCEPT);
1222   if (fe != (FE_OVERFLOW | FE_INEXACT))
1223     {
1224       printf ("long double overflow test failed: %x\n", fe);
1225       result = 1;
1226     }
1227 # endif
1228 #endif
1229
1230 #if !defined NO_LONG_DOUBLE && LDBL_MANT_DIG == 113
1231   volatile long double ld3 = 0x1.0000000000010000000100000001p+1;
1232   volatile long double ld4 = 0x1.0000000000000000000000000001p+1;
1233   (void) &ld3;
1234   (void) &ld4;
1235   ld3 -= ld4;
1236   if (ld3 != 0x1.0p-47)
1237     {
1238       printf ("long double subtraction test failed %.28La\n", ld3);
1239       result = 1;
1240     }
1241 #endif
1242
1243 /* Skip testing IBM long double format, for 2 reasons:
1244    1) it only supports FE_TONEAREST
1245    2) nextafter (0.0, 1.0) == nextafterl (0.0L, 1.0L), so
1246       nextafter (0.0, 1.0) / 16.0L will be 0.0L.  */
1247 #if !defined NO_LONG_DOUBLE && LDBL_MANT_DIG >= DBL_MANT_DIG + 4 \
1248     && LDBL_MANT_DIG != 106
1249   int oldmode = fegetround ();
1250   int j;
1251   for (j = 0; j < 4; j++)
1252     {
1253       int mode;
1254       int i;
1255       int k = 0;
1256       const char *mstr;
1257       switch (j)
1258         {
1259 #ifdef FE_TONEAREST
1260         case 0:
1261           mode = FE_TONEAREST;
1262           mstr = "nearest";
1263           k = 8;
1264           break;
1265 #endif
1266 #ifdef FE_DOWNWARD
1267         case 1:
1268           mode = FE_DOWNWARD;
1269           mstr = "-inf";
1270           break;
1271 #endif
1272 #ifdef FE_UPWARD
1273         case 2:
1274           mode = FE_UPWARD;
1275           mstr = "+inf";
1276           k = 15;
1277           break;
1278 #endif
1279 #ifdef FE_TOWARDZERO
1280         case 3:
1281           mode = FE_TOWARDZERO;
1282           mstr = "0";
1283           break;
1284 #endif
1285         default:
1286           continue;
1287         }
1288
1289       volatile long double ld5 = nextafter (0.0, 1.0) / 16.0L;
1290       volatile double d5;
1291       (void) &ld5;
1292       for (i = 0; i <= 32; i++)
1293         {
1294           if (fesetround (mode))
1295             {
1296               printf ("failed to set rounding mode to %s\n", mstr);
1297               result = 1;
1298               break;
1299             }
1300           d5 = ld5 * i;
1301           (void) &d5;
1302           fesetround (oldmode);
1303           if (d5 != ((j == 0 && i == 8) ? 0 : (i + k) / 16)
1304                     * nextafter (0.0, 1.0))
1305             {
1306               printf ("%La incorrectly rounded to %s as %a\n",
1307                       ld5 * i, mstr, d5);
1308               result = 1;
1309             }
1310         }
1311     }
1312
1313   volatile long double ld7 = nextafterl (0.0L, 1.0L);
1314   volatile double d7;
1315   (void) &ld7;
1316   fesetround (FE_UPWARD);
1317   d7 = ld7;
1318   (void) &d7;
1319   fesetround (oldmode);
1320
1321   if (d7 != nextafter (0.0, 1.0))
1322     {
1323       printf ("%La incorrectly rounded upward to %a\n", ld7, d7);
1324       result = 1;
1325     }
1326 #endif
1327
1328   return result;
1329 }