source: vendor/glibc-tests/glibc/math/bug-tgmath1.c

#include <stdio.h>
#include <tgmath.h>


int
main (void)
{
  int retval = 0;

#define TEST(expr, res) \
  if (sizeof (expr) != res)                                                   \
    {                                                                         \
      printf ("sizeof(%s) == %zu, expected %zu\n", #expr,                     \
              sizeof (expr), (size_t) (res));                                 \
      retval = 1;                                                                     \
    }

  TEST (creal (1.0), sizeof (double));
  TEST (creal (1.0 + 1.0i), sizeof (double));
  TEST (creal (1.0l), sizeof (long double));
  TEST (creal (1.0l + 1.0li), sizeof (long double));
  TEST (creal (1.0f), sizeof (float));
  TEST (creal (1.0f + 1.0fi), sizeof (float));

  TEST (cimag (1.0), sizeof (double));
  TEST (cimag (1.0 + 1.0i), sizeof (double));
  TEST (cimag (1.0l), sizeof (long double));
  TEST (cimag (1.0l + 1.0li), sizeof (long double));
  TEST (cimag (1.0f), sizeof (float));
  TEST (cimag (1.0f + 1.0fi), sizeof (float));

  TEST (fabs (1.0), sizeof (double));
  TEST (fabs (1.0 + 1.0i), sizeof (double));
  TEST (fabs (1.0l), sizeof (long double));
  TEST (fabs (1.0l + 1.0li), sizeof (long double));
  TEST (fabs (1.0f), sizeof (float));
  TEST (fabs (1.0f + 1.0fi), sizeof (float));

  TEST (carg (1.0), sizeof (double));
  TEST (carg (1.0 + 1.0i), sizeof (double));
  TEST (carg (1.0l), sizeof (long double));
  TEST (carg (1.0l + 1.0li), sizeof (long double));
  TEST (carg (1.0f), sizeof (float));
  TEST (carg (1.0f + 1.0fi), sizeof (float));

  return retval;
}