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/*
	Subject: Uninitialized address for temporary (SPARC, gcc 2.3.3)


		Variables f1, f2, f3 contain successive results of
	a floating point function.  Since SPARC floating point 
	registers are not preserved by function calls, 
	gcc -O (version 2.3.3) moves f1 to %l4 and f2 to %l2.
	Later, when f1, f2, and f3 are used in a computation,
	address [%o3] is used to move f1 back to a floating
	point register, but %o3 has not been initialized.
	
		The problem occurs only if the program
	has lots of local data, and a displacement over
	12-bits might be required on the temporary.

		Peter Montgomery
		Department of Mathematics
		Oregon State University
		Corvallis, OR 97331-4605
		pmontgom@math.orst.edu

	Specifically, the generated code (SPARC, SunOS 4.1.1) contains

L6:
        call _printf,0
        mov %l2,%o1			itest (for printf)
        call _drand48,0
        add %l2,1,%l2			itest++
        std %f0,[%fp-8]
        ldd [%fp-8],%l4			%l4 = f1
        call _drand48,0
        nop
        std %f0,[%fp-8]
        ldd [%fp-8],%l0			%l0 = f2
        call _drand48,0
        nop
        std %l4,[%o3]			***** %o3 undefined *****
        ldd [%o3],%f4			Attempting to move f1 to %f4
        sethi %hi(-5024),%o3
        or %o3,%lo(-5024),%o3
        add %o3,%fp,%o3
        std %l0,[%o3]
        ldd [%o3],%f6			%f6 = f2
        faddd %f4,%f6,%f2		%f2 = f1 + f2
        faddd %f2,%f0,%f0		%f0 = f1 + f2 + f3
        std %f0,[%fp-8]
        ld [%fp-4],%o2
        ld [%fp-8],%o1
        call _printf,0			Print f1 + f2 + f3
        or %l3,%lo(LC1),%o0

*/
double drand48();		/* SUN random number generator */
/* #include <stdio.h> */

int main(int argc, char* argv[])
{
#if 1			/* Works if this is removed */
    char unused[5000];
#endif
    double f1, f2, f3;
    int itest; 
    for (itest = 1; itest <= 10 ; itest++) {
	printf("Iteration %d\n", itest);
        f1 = drand48(); 
        f2 = drand48(); 
        f3 = drand48();
	printf("Random sum: %6f\n", f1 + f2 + f3);
    }					 
    exit(0);
}