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I've encountered trouble with the initialization of nonlocal static
objects.  The following parts of the ARM are relevant:

  ARM 3.4
  The initialization of nonlocal static objects in a translation unit is
  done before the first use of any function or object defined in that
  translation unit.  Such initializations may be done before the first
  statement of main() or deferred to any point in time before the first
  use of a function or object defined in that translation unit.  The
  default initialization of all static objects to zero is performed
  before any dynamic (that is, run-time) initialization.  No further
  order is imposed on the initialization of objects from different
  translation units.
  
  ARM 3.4 annotation
  A useful technique for insuring that a global object is initialized
  only once and before its first use is to maintain a count of the
  number of translation units using it.
  
  ARM 7.1.6
  A const object may be initialized, but its value may not be changed 
  thereafter.

Are the following observations correct?

  The technique described in the ARM 3.4 annotation cannot be applied to
  const objects since the values of the objects may not be changed.

  The ARM 3.4 guarantee that the "initialization of nonlocal static
  objects in a translation unit is done before the first use of any
  function or object defined in that translation unit" is not accurate.
  Functions or objects defined in a translation unit may be used in the
  initialization of nonlocal static objects defined in other translation
  units.  Therefore, mutual dependencies may make it impossible to honor 
  the guarantee.

  The C++ standard could be revised to include a guarantee that whenever
  possible, the initialization of nonlocal static objects in a translation 
  unit is done before any function or object in that translation unit is 
  used to initialize objects in other translation units.  Otherwise, 
  const objects should not be used.

The Sun SPARCompiler C++ 4.1 and G++ 2.7.2 don't even honor the ARM
guarantee when there are no mutual dependencies.  The following
example illustrates the problem.  There are four files: library.cc,
library.h, luser.cc, and main.cc.  The behavior of the program depends
on the order in which files are specified in the compile command:

gator jgealow % $CC main.cc luser.cc library.cc
gator jgealow % ./a.out
global: 0
local: 6

gator jgealow % $CC main.cc library.cc luser.cc
gator jgealow % ./a.out
global: 6
local: 6

Jeff


::::::::::::::
library.h
::::::::::::::
class X {
public:
  int i;
  X(int);
};

class Y {
public:
  int i;
  Y();
};
::::::::::::::
library.cc
::::::::::::::
#include "library.h"

const X Int_(0);
const X Int0(1);
const X Int1(2);
const X Intx(3);

X :: X( int x) : i(x)
{}

Y :: Y( )
{
  i = Int_.i + Int0.i + Int1.i + Intx.i;
}
::::::::::::::
luser.cc
::::::::::::::
#include "library.h"

Y global;
::::::::::::::
main.cc
::::::::::::::
#include <iostream.h>

#include "library.h"

extern Y global;

int main(int, char* argv[])
{
  Y local;
  cout << "global: " << global.i << endl;
  cout << "local: " << local.i << endl;
}
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