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#include <fenv.h>
#include <stdio.h>
double stop_constant_propagation(double x)
{
// asm volatile ("" : "+mx"(x)); return x;
asm volatile ("" : "=m"(x) : "m"(x)); return x;
// volatile double y = x; return y;
}
double force_to_double(double x)
{
#if defined __i386__ || defined __ia64__
// asm volatile ("" : "+mx"(x)); return x;
asm volatile ("" : "=m"(x) : "m"(x)); return x;
// volatile double y = x; return y;
#else
return x;
#endif
}
int main()
{
fesetround(FE_UPWARD);
double lhs = -force_to_double((-1.1) * stop_constant_propagation(10.1));
double rhs = force_to_double(( 1.1) * stop_constant_propagation(10.1));
printf( "%s\n", lhs != rhs ? "lhs != rhs (correct)" : "lhs == rhs (error)");
return lhs != rhs ? 0 : 1;
}
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