Python 3.7 build (#381)

* Updated for Python 3.7.1

recipes/python3crystax/libffi/testsuite/libffi.call/struct6.c

@@ -0,0 +1,64 @@
+/* Area:	ffi_call
+   Purpose:	Check structures.
+   Limitations:	none.
+   PR:		none.
+   Originator:	From the original ffitest.c  */
+
+/* { dg-do run } */
+#include "ffitest.h"
+typedef struct
+{
+  float f;
+  double d;
+} test_structure_6;
+
+static test_structure_6 ABI_ATTR struct6 (test_structure_6 ts)
+{
+  ts.f += 1;
+  ts.d += 1;
+  
+  return ts;
+}
+
+int main (void)
+{
+  ffi_cif cif;
+  ffi_type *args[MAX_ARGS];
+  void *values[MAX_ARGS];
+  ffi_type ts6_type;
+  ffi_type *ts6_type_elements[3];
+
+  test_structure_6 ts6_arg;
+
+  /* This is a hack to get a properly aligned result buffer */
+  test_structure_6 *ts6_result =
+    (test_structure_6 *) malloc (sizeof(test_structure_6));
+
+  ts6_type.size = 0;
+  ts6_type.alignment = 0;
+  ts6_type.type = FFI_TYPE_STRUCT;
+  ts6_type.elements = ts6_type_elements;
+  ts6_type_elements[0] = &ffi_type_float;
+  ts6_type_elements[1] = &ffi_type_double;
+  ts6_type_elements[2] = NULL;
+
+  args[0] = &ts6_type;
+  values[0] = &ts6_arg;
+
+  /* Initialize the cif */
+  CHECK(ffi_prep_cif(&cif, ABI_NUM, 1, &ts6_type, args) == FFI_OK);
+  
+  ts6_arg.f = 5.55f;
+  ts6_arg.d = 6.66;
+  
+  printf ("%g\n", ts6_arg.f);
+  printf ("%g\n", ts6_arg.d);
+
+  ffi_call(&cif, FFI_FN(struct6), ts6_result, values);
+    
+  CHECK(ts6_result->f == 5.55f + 1);
+  CHECK(ts6_result->d == 6.66 + 1);
+    
+  free (ts6_result);
+  exit(0);
+}