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/*
Date: 25 Jan 89 14:43:05 GMT
From: meyering@cs.utexas.edu (Jim Meyering)
Subject: 1.32 sun4os4 bug-- passing structures
Message-Id: <150@ai.cs.utexas.edu>
To: bug-gcc@prep.ai.mit.edu
*/
/*
* gcc-1.32 (sun4-os4) has a problem passing structure arguments.
*
* If the type FLT is changed to float, all problems disappear.
*
* If PRINTF is defined and -O is *not* used, the program terminates
* with a segmentation fault. In all other cases I've tried, the
* program runs, but the arguments to foo are not properly copied.
* To be precise, in foo, the value that one would normally expect
* to find in b.y is overwritten with that of b.x. (see output in
* comments below)
*/
typedef double FLT;
typedef struct point { FLT x, y; } PT;
#define N 4
FLT x[N];
#if defined(PRINTF)
#define PRINT(a) for (i=0;i<N;i++) printf("%g ", (a)[i]); printf("\n");
#endif
#if defined(FPRINTF) || !defined(PRINTF)
#include <stdio.h>
#define PRINT(a) for (i=0;i<N;i++) fprintf(stdout,"%g ", (a)[i]); \
fprintf(stdout,"\n");
#endif
void
main()
{
int bad,i;
PT s,t;
FLT w[N];
void foo(PT,PT);
s.x = 0;
s.y = 1;
t.x = 999;
t.y = 3;
w[0] = s.x; w[1] = s.y;
w[2] = t.x; w[3] = t.y;
foo(s,t);
bad = -1;
for (i=0;i<N;i++) {
if (w[i] != x[i]) {
bad = i;
break;
}
}
if (bad >= 0) {
PRINT(w);
PRINT(x);
} else {
printf("Test passed.\n");
}
exit(0);
}
void
foo(PT a,PT b)
{
extern FLT x[N];
x[0] = a.x;
x[1] = a.y;
x[2] = b.x;
x[3] = b.y;
}
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