Re: [Qemu-devel] [PATCH v3 04/10] tcg: Introduce atomic helpers for integer min/max

[Peter Maydell]

On 8 May 2018 at 18:49, Peter Maydell <address@hidden> wrote:
> [weird compiler errors]

This fixes them:

--- a/include/qemu/atomic.h
+++ b/include/qemu/atomic.h
@@ -187,7 +187,7 @@
 /* Returns the eventual value, failed or not */
 #define atomic_cmpxchg__nocheck(ptr, old, new)    ({                    \
     typeof_strip_qual(*ptr) _old = (old);                               \
-    __atomic_compare_exchange_n(ptr, &_old, new, false,                 \
+    (void)__atomic_compare_exchange_n(ptr, &_old, new, false,           \
                               __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST);      \
     _old;                                                               \
 })

Seems pretty clearly a compiler bug -- rth says newer gcc don't
do this, so presumably fixed upstream somewhere between gcc 5 and 6.

thanks
-- PMM