boost::spirit concurrency gap

[vlad_news@…]

The following snipped code from the "boost::spirit" library contains the problem with concurrent access to a static object. Creation of a object of "thread_specific_ptr" type should be protected while concurrent access is performed.

boost\spirit\core\non_terminal\impl\grammar.ipp

...

# ifdef BOOST_SPIRIT_THREADSAFE

should be protected with a "call once" idiom

static boost::thread_specific_ptr<ptr_t> tld_helper;

if (!tld_helper.get())

tld_helper.reset(new ptr_t);

ptr_t &helper = *tld_helper;

# else

static ptr_t helper;

# endif

...

[anonymous]

Fix applied.