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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;
}
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