Compiler error OR missing error message

[Philippe Bouchard]

The following program:
#include <iostream>
int main()
{
  int a[] = {0, 1, 2, a[0]};
  std::cout << a[0] << ", " << a[1] <<
", " << a[2] << ", " << a[3] << std::endl;
}
Outputs:
0, 1, 2, 1074463848
Under:
Reading specs from /usr/lib/gcc-lib/i386-linux/2.95.2/specs
gcc version 2.95.2 20000220 (Debian GNU/Linux)
This is either a compiler error, because the a[0] is supposed to be
initialized when initializing a[3], or I am trying to access an undefined
variable and the compiler or not reporting so.
Thank you.
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