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/* { dg-options "-fnon-call-exceptions" } */
/* With -fnon-call-exceptions 0 / 0 should not be eliminated. */
/* { dg-additional-options "-DSIGNAL_SUPPRESS" { target { ! signal } } } */
/* { dg-additional-options "-mcheck-zero-division" { target { loongarch*-*-* } } } */
#ifdef SIGNAL_SUPPRESS
# define DO_TEST 0
#elif defined (__powerpc__) || defined (__PPC__) || defined (__ppc__) || defined (__POWERPC__) || defined (__ppc)
/* On PPC division by zero does not trap. */
# define DO_TEST 0
#elif defined (__riscv)
/* On RISC-V division by zero does not trap. */
# define DO_TEST 0
#elif defined (__sh__)
/* On SH division by zero does not trap. */
# define DO_TEST 0
#elif defined (__v850__)
/* On V850 division by zero does not trap. */
# define DO_TEST 0
#elif defined (__MSP430__)
/* On MSP430 division by zero does not trap. */
# define DO_TEST 0
#elif defined (__RL78__)
/* On RL78 division by zero does not trap. */
# define DO_TEST 0
#elif defined (__RX__)
/* On RX division by zero does not trap. */
# define DO_TEST 0
#elif defined (__aarch64__)
/* On AArch64 integer division by zero does not trap. */
# define DO_TEST 0
#elif defined (__TMS320C6X__)
/* On TI C6X division by zero does not trap. */
# define DO_TEST 0
#elif defined (__VISIUM__)
/* On Visium division by zero does not trap. */
# define DO_TEST 0
#elif defined (__mips__) && !defined(__linux__)
/* MIPS divisions do trap by default, but libgloss targets do not
intercept the trap and raise a SIGFPE. The same is probably
true of other bare-metal environments, so restrict the test to
systems that use the Linux kernel. */
# define DO_TEST 0
#elif defined (__mips16) && defined(__linux__)
/* Not all Linux kernels deal correctly the breakpoints generated by
MIPS16 divisions by zero. They show up as a SIGTRAP instead. */
# define DO_TEST 0
#elif defined (__MICROBLAZE__)
/* We cannot rely on division by zero generating a trap. */
# define DO_TEST 0
#elif defined (__epiphany__)
/* Epiphany does not have hardware division, and the software implementation
has truly undefined behavior for division by 0. */
# define DO_TEST 0
#elif defined (__m68k__) && !defined(__linux__)
/* Attempting to trap division-by-zero in this way isn't likely to work on
bare-metal m68k systems. */
# define DO_TEST 0
#elif defined (__CRIS__)
/* No SIGFPE for CRIS integer division. */
# define DO_TEST 0
#elif defined (__MMIX__)
/* By default we emit a sequence with DIVU, which "never signals an
exceptional condition, even when dividing by zero". */
# define DO_TEST 0
#elif defined (__arc__)
/* No SIGFPE for ARC integer division. */
# define DO_TEST 0
#elif defined (__arm__) && defined (__ARM_EABI__)
# ifdef __ARM_ARCH_EXT_IDIV__
/* Hardware division instructions may not trap, and handle trapping
differently anyway. Skip the test if we have those instructions. */
# define DO_TEST 0
# else
# include <signal.h>
/* ARM division-by-zero behavior is to call a helper function, which
can do several different things, depending on requirements. Emulate
the behavior of other targets here by raising SIGFPE. */
int __attribute__((used))
__aeabi_idiv0 (int return_value)
{
raise (SIGFPE);
return return_value;
}
# define DO_TEST 1
# endif
#elif defined (__nios2__)
/* Nios II requires both hardware support and user configuration to
raise an exception on divide by zero. */
# define DO_TEST 0
#elif defined (__nvptx__)
/* There isn't even a signal function. */
# define DO_TEST 0
#elif defined (__csky__)
/* This presently doesn't raise SIGFPE even on csky-linux-gnu, much
less bare metal. See the implementation of __divsi3 in libgcc. */
# define DO_TEST 0
#elif defined (__moxie__)
/* Not all moxie configurations may raise exceptions. */
# define DO_TEST 0
#elif defined (__or1k__)
/* On OpenRISC division by zero does not trap. */
# define DO_TEST 0
#elif defined (__pru__)
/* There isn't even a signal function. */
# define DO_TEST 0
#else
# define DO_TEST 1
#endif
extern void abort (void);
extern void exit (int);
#if DO_TEST
#include <signal.h>
void
sigfpe (int signum __attribute__ ((unused)))
{
exit (0);
}
#endif
/* When optimizing, the compiler is smart enough to constant fold the
static unset variables i and j to produce 0 / 0, but it can't
eliminate the assignment to the global k. */
static int i;
static int j;
int k __attribute__ ((used));
int
main ()
{
#if DO_TEST
signal (SIGFPE, sigfpe);
k = i / j;
abort ();
#else
exit (0);
#endif
}
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