id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
9426	boost::atomic gcc-cas related specializations patch	Piotr Kobzda <pikob@…>	timblechmann	"Patch adds **''BOOST_ATOMIC_ALLOW_GCC_CAS''** library configuration option causing preferred use of atomic implementation specializations from ''gcc-cas.hpp'' instead of default ones.

Patch includes also all changes necessary to fix compilation problems of ''gcc-cas.hpp'', and ''cas32strong.hpp''.

Tested with gcc 4.5.3 (and few earlier versions) on ARM (manually forced) and on mipsel platforms.

The gcc-cas atomic specializations (full memory barrier based) appeared to perform better on platforms where the default ones where used (pthread mutex based ones).

However, the original author has disabled gcc-cas specialization with the following comment:

  ''/* currently does not work correctly */''

which is a good reason for making use of it optional so far.

Anyway, it would be great to know the details of the problems related the above comment, which could help in deciding if a new option can be used (and possibly help in solving of the issue)."	Patches	closed	To Be Determined	atomic	Boost 1.55.0	Problem	fixed		Andrey.Semashev@…