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/*
** float-union-assignment.cpp
**
** Martin Brain
** martin.brain@cs.ox.ac.uk
** 26/09/12
**
** A reduced test case for problems with returning and assigning fields in a union.
**
*/
#include <assert.h>
#include <stdint.h>
typedef struct _components {
unsigned int negative:1;
unsigned int exponent:8;
unsigned int mantissa:23;
} components;
typedef union _ieee754_float {
components ieee;
float f;
} ieee754_float;
float returnsField (uint32_t index) {
ieee754_float c;
c.ieee.negative = index & 0x1;
c.ieee.exponent = 0;
c.ieee.mantissa = 0;
return c.f;
}
ieee754_float returnsStructure (uint32_t index) {
ieee754_float c;
c.ieee.negative = index & 0x1;
c.ieee.exponent = 0;
c.ieee.mantissa = 0;
return c;
}
void testOne (void) {
ieee754_float f1, f2;
f1 = returnsStructure(0);
f2 = returnsStructure(1);
assert(f1.ieee.negative != f2.ieee.negative);
return;
}
void testTwo (void) {
ieee754_float f1, f2;
f1 = returnsStructure(0);
f2 = returnsStructure(1);
assert(f1.ieee.negative != f2.ieee.negative);
f1.f = returnsField(0);
f2.f = returnsField(1);
assert(f1.ieee.negative != f2.ieee.negative);
return 1;
}
int testThree (void) {
ieee754_float f1, f2;
f1.f = returnsField(0);
f2.f = returnsField(1);
assert(f1.ieee.negative != f2.ieee.negative);
return 1;
}
int main (void) {
testOne();
testTwo();
testThree();
return 0;
}
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