id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
2525	More architectures that do not support __sync_fetch_and_add_4	Steven Robbins <smr@…>	Peter Dimov	"Hi,

As noted in #2263, Boost makes the incorrect assumption that if the following condition is true:

defined( GNUC ) && ( GNUC * 100 + GNUC_MINOR >= 401 )

then GCC sync primitives (e.g. sync_lock_test_and_set, sync_fetch_and_add) are available. 

Currently, hppa and arm are listed as exceptions.  However, building Boost on Debian's 14 architectures suggests that some more exceptions are needed: __armel__ (ARM in little endian mode), __m68k__ and __sparc__.  I'm attaching a patch to atomic_count.hpp to this effect.

When using GNU C++ however, that patch means that all those machines fall through to atomic_count_gcc.hpp, which is known to be broken for GCC > 4.1 (c.f. #1084, never applied).  I'm attaching a patch for this problem, too.

Note that these patches are only for the problems I noticed while building Boost, and only because we also build ""tools/bcp"", which happens to use shared_ptr.  From grepping the sources it appears that there are a few others.
"	Bugs	closed	Boost 1.39.0	smart_ptr	Boost 1.37.0	Problem	fixed