Re: [boost] ARM platform: undefined reference to __sync_fetch_and_add_4

From: Vladimir Prus (ghost_at_[hidden])
Date: 2008-04-04 09:08:35

Schrader, Glenn wrote:

>> > With assistance on the boost-build list I've ascertained that the
>> > problem is that GCC doesn't support __sync_fetch_and_add and the other
>> > atomic built-ins on ARM.

>> Two workarounds are available: define BOOST_SP_DISABLE_THREADS to disable
>> MT-safety for the reference count, or define BOOST_SP_USE_PTHREADS to use
>> a
>> pthread_mutex.
>>

> Another option would be to just supply the __sync_fetch_and_add_4 function that gcc is trying to
> link in. When gcc doesn't support the builtin it assumes that a function exists with that name. A
> snippet of ARM assembly to implement the atomic operation shouldn't be that difficult.

Are you volunteering to write such a "snippet"?

- Volodya