GCC not doing the correct thing?

FROM : Andrew Yager
DATE : Thu Nov 07 21:53:01 2002

Hi,

The following code snippet does not appear to function correctly.

#include <stdio.h>
#define cube(x) x*x*x

int main()
{
int x=1;
int y=2;
int z=3;
int* ptr = &z;

printf("%d\n", *ptr);
printf("%d\n", ptr);
printf("%d\n", cube(*ptr++));
printf("%d\n", *ptr);
printf("%d\n", ptr);


}

--

The preprocess code outputted from cpp is:

# 2 "test.c" 2 3


int main()
{
int x=1;
int y=2;
int z=3;
int* ptr = &z;

printf("%d\n", *ptr);
printf("%d\n", ptr);
printf("%d\n", *ptr++**ptr++**ptr++);
printf("%d\n", *ptr);
printf("%d\n", ptr);


}

However when compiled with ³Apple Computer, Inc. GCC version 1151, based on
gcc version 3.1 20020420 (prerelease),² the following is the output:

3
-1073742488
27
-1073742484
-1073742484

You can see on examination that this should not work... At least if it does
work, it shouldn¹t work in this way...!!!!

Sorry for the uninformative error report... Someone with more skill at these
should perhaps do it...

Yours,
Andrew

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Andrew Yager
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