gcc/testsuite/gcc.dg/torture/float128-extendxf-underflow.c

   1 /* Test that extension from XFmode to __float128 raises underflow for
   2    exact tiny values, if trapping on underflow is enabled.  */
   3
   4 /* { dg-do run { target i?86-*-*gnu* x86_64-*-*gnu* ia64-*-*gnu* } } */
   5 /* { dg-options "-D_GNU_SOURCE" } */
   6 /* { dg-require-effective-target fenv_exceptions } */
   7
   8 #include <fenv.h>
   9 #include <setjmp.h>
  10 #include <signal.h>
  11 #include <stdlib.h>
  12
  13 volatile sig_atomic_t caught_sigfpe;
  14 sigjmp_buf buf;
  15
  16 static void
  17 handle_sigfpe (int sig)
  18 {
  19   caught_sigfpe = 1;
  20   siglongjmp (buf, 1);
  21 }
  22
  23 int
  24 main (void)
  25 {
  26   volatile long double a = 0x1p-16384L;
  27   volatile __float128 r;
  28   r = a;
  29   if (fetestexcept (FE_UNDERFLOW))
  30     abort ();
  31   if (r != 0x1p-16384q)
  32     abort ();
  33   feenableexcept (FE_UNDERFLOW);
  34   signal (SIGFPE, handle_sigfpe);
  35   if (sigsetjmp (buf, 1) == 0)
  36     r = a;
  37   if (!caught_sigfpe)
  38     abort ();
  39   exit (0);
  40 }