mirrors/qemu
0
0
Fork 0
mirror of https://github.com/qemu/qemu.git synced 2024-11-24 11:23:43 +08:00
Code Issues Packages Projects Releases Wiki Activity

atomic.h: Fix build with clang

Browse Source 
clang defines __ATOMIC_SEQ_CST but its implementation of the
__atomic_exchange() builtin differs from that of gcc. Move the
__clang__ branch of the ifdef ladder to the top and fix its
implementation (there is no such builtin as __sync_exchange),
so we can compile with clang again.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Peter Maydell 2013-10-22 10:58:41 +01:00 committed by Paolo Bonzini
parent 7839ff593b
commit 392a4d5b9a
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/qemu/atomic.h
View File

@ -168,14 +168,14 @@
#endif
#ifndef atomic_xchg
#ifdef __ATOMIC_SEQ_CST
#if defined(__clang__)
#define atomic_xchg(ptr, i) __sync_swap(ptr, i)
#elif defined(__ATOMIC_SEQ_CST)
#define atomic_xchg(ptr, i) ({ \
typeof(*ptr) _new = (i), _old; \
__atomic_exchange(ptr, &_new, &_old, __ATOMIC_SEQ_CST); \
_old; \
})
#elif defined __clang__
#define atomic_xchg(ptr, i) __sync_exchange(ptr, i)
#else
/* __sync_lock_test_and_set() is documented to be an acquire barrier only. */
#define atomic_xchg(ptr, i) (smp_mb(), __sync_lock_test_and_set(ptr, i))