Re: Confused about a thread-safe singleton example.

James Kanze <>
Wed, 3 Dec 2008 14:25:48 -0800 (PST)
On Dec 3, 6:27 pm, ""
<> wrote:

On Dec 3, 4:53 am, James Kanze <> wrote:

On Dec 3, 1:25 am, ""

I have another question, on the subject of static
initialization order in general, not thread safety. Is it
guaranteed that statics in a given translation unit will be
initialized before the first time a function in that
translation unit is called? E.g. if I have this:

static TheClass *ourInstance = new TheClass;

TheClass & TheClass::instance () {
  return *ourInstance;

Even I call TheClass::instance() during static initialization
of another object that was initialized first, will simply
calling that function guarantee that ourInstance will be
initialized in time?

NO. That's what we mean when we speak of the order of
initialization problem. That's why we have a pointer, which we
test for null, or we use a local static, or some other solution
in which the function constructs the first time it is called.

James Kanze (GABI Software)
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