* atomic.h (ATOMIC_INC, ATOMIC_DEC): return old values.

  [ruby-dev:44596] [Bug #5439]
* signal.c (ruby_atomic_exchange): no needs to define on the
  platforms where atomic.h is available.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@33464 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 2 deletions

diff --git a/atomic.h b/atomic.h
index d131677aa6..33f731927d 100644
--- a/atomic.h
+++ b/atomic.h
@@ -54,11 +54,12 @@ typedef unsigned int rb_atomic_t;
 
 #else
 typedef int rb_atomic_t;
+#define NEED_RUBY_ATOMIC_EXCHANGE
 extern rb_atomic_t ruby_atomic_exchange(rb_atomic_t *ptr, rb_atomic_t val);
 
 # define ATOMIC_SET(var, val) (void)((var) = (val))
-# define ATOMIC_INC(var) (++(var))
-# define ATOMIC_DEC(var) (--(var))
+# define ATOMIC_INC(var) ((var)++)
+# define ATOMIC_DEC(var) ((var)--)
 # define ATOMIC_OR(var, val) ((var) |= (val))
 # define ATOMIC_EXCHANGE(var, val) ruby_atomic_exchange(&(var), (val))
 #endif