Agustín K-ballo Bergé wrote:

Is the following code supposed to work (instead of resulting on a stack overflow)? If so, what I'm doing wrong? I'm using Boost 1.37.0 on MS Visual Studio 2008, Windows.

Do you have a real use case for this type of code? I'm not sure what you would expect this to do. A reasonable call_once would only set initialization_flag once call_me_once() actually completes otherwise call_once is useless. I don't think once_flag can be used as a local static because the standard does not guarantee static initialization for non-const local statics. Or atleast it didn't the last time I looked it up! BOOST_ONCE_INIT is supposed to be statically initialized. I'm not sure if that has changed or not in recent releases. I'm pretty sure it wouldn't change else it would break a lot of code.

#include

boost::once_flag initialization_flag = BOOST_ONCE_INIT;

void call_me_once() { boost::call_once( initialization_flag, call_me_once ); }

int main( int, char*[] ) { boost::call_once( initialization_flag, call_me_once );

return 0; }

Additionaly,

- Can a once_flag be safelly used in a class or local static? - Is BOOST_ONCE_INIT guaranteed to statically initialize the flag?

Agustín K-ballo Bergé.-

-- Sohail Somani http://uint32t.blogspot.com