[cfe-dev] How to disable built-in?

[Dmitri Shubin]

Hello!

When building Berkeley DB (checked 4.8.30 and 5.1.25) with clang (trunk) 
I got the following error:

In file included from 
/export/home/sbn/thd/25/src/thirdparty/BerkeleyDB/5.1.25/src/src/mutex/mut_pthread.c:11:
In file included from ./db_int.h:999:
In file included from 
/export/home/sbn/thd/25/src/thirdparty/BerkeleyDB/5.1.25/src/src/dbinc/mutex.h:15:
In file included from 
/export/home/sbn/thd/25/src/thirdparty/BerkeleyDB/5.1.25/src/src/dbinc/mutex_int.h:12:
/export/home/sbn/thd/25/src/thirdparty/BerkeleyDB/5.1.25/src/src/dbinc/atomic.h:179:19: 
error: definition of builtin function '__atomic_compare_exchange'
static inline int __atomic_compare_exchange(
                   ^
1 error generated.

AFAIU this built-in was added rather recently since I was able to build 
it with clang a month or so ago.

Is there any way to disable this built-in?
'-fno-builtin' doesn't help.

(Yes, I know that it's bad idea to start identifiers with underscores)