[Haifux] Intermingled code and declarations and gcc

[Eli Billauer]

Hi,


Yes, it's C. The problem occurred when going through the standard 
configure/make procedure for gphoto2-2.3.1, and I'm positive that the 
attempt to compile was with gcc (and it blew on this problem). The file 
is gp-params.c. The date on the file is December 2006 (so it should work 
with an old compiler).


Obviously, some people managed to compile this. I wonder what their 
magic was.

The problem is *not* that the size of the declared array depends on a 
runtime variable. This compiles and runs (using uninitialized memory, 
but who cares):

#include <stdio.h>
int main(int argc, char *argv[]) {

  char my_array[argc];
  printf("%d", my_array[0]);
  return 0;
}

This doesn't compile at all:

#include <stdio.h>
int main(int argc, char *argv[]) {
  unsigned int my_count;

  for (my_count=0; argv[my_count] != NULL; my_count++);
 
  char my_array[my_count];
  printf("%d", my_array[0]);

  return 0;
}

Ideas? I suppose this issue arises every now and then when compiling 
code written by wild programmers.

   Eli

Orna Agmon Ben-Yehuda wrote:

> Hi Eli,
>
> Is this C? You are defining an array with an unknown length at compile
> time. It won't work anyhow, no matter what the value of the length var
> is. You need a malloc there.
>
> Unless this is C++ with some overriding?
>
> Orna.
>
>   


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