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/* Copyright 2002 Free Software Foundation, Inc.

   Tests correct signedness of operations on bitfields; in particular

   that integer promotions are done correctly, including the case when

   casts are present.

   The C front end was eliding the cast of an unsigned bitfield to

   unsigned as a no-op, when in fact it forces a conversion to a

   full-width unsigned int. (At the time of writing, the C++ front end

   has a different bug; it erroneously promotes the uncast unsigned

   bitfield to an unsigned int).

   Source: Neil Booth, 25 Jan 2002, based on PR 3325 (and 3326, which

   is a different manifestation of the same bug).

*/

extern void abort ();

int

main(int argc, char *argv[])

{

  struct x { signed int i : 7; unsigned int u : 7; } bit;

  unsigned int u;

  int i;

  unsigned int unsigned_result = -13U % 61;

  int signed_result = -13 % 61;

  bit.u = 61, u = 61;

  bit.i = -13, i = -13;

  if (i % u != unsigned_result)

    abort ();

  if (i % (unsigned int) u != unsigned_result)

    abort ();

  /* Somewhat counter-intuitively, bit.u is promoted to an int, making

     the operands and result an int.  */

  if (i % bit.u != signed_result)

    abort ();

  if (bit.i % bit.u != signed_result)

    abort ();

  /* But with a cast to unsigned int, the unsigned int is promoted to

     itself as a no-op, and the operands and result are unsigned.  */

  if (i % (unsigned int) bit.u != unsigned_result)

    abort ();

  if (bit.i % (unsigned int) bit.u != unsigned_result)

    abort ();

  return 0;

}