#include <stdio.h>
#include <stdlib.h>
#include <sys/auxv.h>

/* Run with/without environment variables does not influence HWCAPs:

   GLIBC_TUNABLES=""
   LD_HWCAP_MASK=""
   HWCAPs passed as argument to ifunc-resolver: 0x67ffff
   HWCAPs from getauxval (AT_HWCAP): 0x67ffff

   GLIBC_TUNABLES="glibc.cpu.hwcap_mask=0"
   LD_HWCAP_MASK=""
   HWCAPs passed as argument to ifunc-resolver: 0x67ffff
   HWCAPs from getauxval (AT_HWCAP): 0x67ffff

   GLIBC_TUNABLES=""
   LD_HWCAP_MASK="0x0"
   HWCAPs passed as argument to ifunc-resolver: 0x67ffff
   HWCAPs from getauxval (AT_HWCAP): 0x67ffff
*/

static unsigned long global_hwcaps = 0;

static int impl(void)
{
  printf ("HWCAPs passed as argument to ifunc-resolver: 0x%lx\n",
	  global_hwcaps);
  return 42;
}
static void *resolver(unsigned long hwcap)
{
  global_hwcaps = hwcap;
  return impl;
}
int ifunc(void) __attribute__((ifunc("resolver")));

int
main (void)
{
  printf ("GLIBC_TUNABLES=\"%s\"\n", getenv ("GLIBC_TUNABLES") ? : "");
  printf ("LD_HWCAP_MASK=\"%s\"\n", getenv ("LD_HWCAP_MASK") ? : "");

  ifunc ();
  printf ("HWCAPs from getauxval (AT_HWCAP): 0x%lx\n", getauxval (AT_HWCAP));

  return EXIT_SUCCESS;
}