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/*
This test checks promotion of bitfields. Bitfields should be promoted
very much like chars and shorts:
Bitfields (signed or unsigned) should be promoted to signed int if their
value will fit in a signed int, otherwise to an unsigned int if their
value will fit in an unsigned int, otherwise we don't promote them (ANSI/ISO
does not specify the behavior of bitfields larger than an unsigned int).
We test the behavior by subtracting two from the promoted value: this will
result in a negitive value for signed types, a positive value for unsigned
types. This test (of course) assumes that the compiler is correctly
implementing signed and unsigned arithmetic.
*/
void abort (void);
void exit (int);
struct X {
unsigned int u3:3;
signed long int s31:31;
signed long int s32:32;
unsigned long int u31:31;
unsigned long int u32:32;
unsigned long long ull3 :3;
unsigned long long ull35:35;
unsigned u15:15;
};
struct X x;
int
main (void)
{
if ((x.u3 - 2) >= 0) /* promoted value should be signed */
abort ();
if ((x.s31 - 2) >= 0) /* promoted value should be signed */
abort ();
if ((x.s32 - 2) >= 0) /* promoted value should be signed */
abort ();
if ((x.u15 - 2) >= 0) /* promoted value should be signed */
abort ();
/* Conditionalize check on whether integers are 4 bytes or larger, i.e.
larger than a 31 bit bitfield. */
if (sizeof (int) >= 4)
{
if ((x.u31 - 2) >= 0) /* promoted value should be signed */
abort ();
}
else
{
if ((x.u31 - 2) < 0) /* promoted value should be UNsigned */
abort ();
}
if ((x.u32 - 2) < 0) /* promoted value should be UNsigned */
abort ();
if ((x.ull3 - 2) >= 0) /* promoted value should be signed */
abort ();
if ((x.ull35 - 2) < 0) /* promoted value should be UNsigned */
abort ();
exit (0);
}
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