Imported Upstream version 2.67.1
[platform/upstream/glib.git] / glib / gatomic.h
index b06b527..e6eccfa 100644 (file)
@@ -1,10 +1,10 @@
 /*
  * Copyright © 2011 Ryan Lortie
  *
- * This library is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * licence, or (at your option) any later version.
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
- * USA.
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  *
  * Author: Ryan Lortie <desrt@desrt.ca>
  */
 
-#if defined(G_DISABLE_SINGLE_INCLUDES) && !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
-#error "Only <glib.h> can be included directly."
-#endif
-
 #ifndef __G_ATOMIC_H__
 #define __G_ATOMIC_H__
 
+#if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
+#error "Only <glib.h> can be included directly."
+#endif
+
 #include <glib/gtypes.h>
 
 G_BEGIN_DECLS
 
-gint                    g_atomic_int_get                      (volatile gint  *atomic);
+GLIB_AVAILABLE_IN_ALL
+gint                    g_atomic_int_get                      (const volatile gint *atomic);
+GLIB_AVAILABLE_IN_ALL
 void                    g_atomic_int_set                      (volatile gint  *atomic,
                                                                gint            newval);
+GLIB_AVAILABLE_IN_ALL
 void                    g_atomic_int_inc                      (volatile gint  *atomic);
+GLIB_AVAILABLE_IN_ALL
 gboolean                g_atomic_int_dec_and_test             (volatile gint  *atomic);
+GLIB_AVAILABLE_IN_ALL
 gboolean                g_atomic_int_compare_and_exchange     (volatile gint  *atomic,
                                                                gint            oldval,
                                                                gint            newval);
+GLIB_AVAILABLE_IN_ALL
 gint                    g_atomic_int_add                      (volatile gint  *atomic,
                                                                gint            val);
+GLIB_AVAILABLE_IN_2_30
 guint                   g_atomic_int_and                      (volatile guint *atomic,
                                                                guint           val);
+GLIB_AVAILABLE_IN_2_30
 guint                   g_atomic_int_or                       (volatile guint *atomic,
                                                                guint           val);
+GLIB_AVAILABLE_IN_ALL
 guint                   g_atomic_int_xor                      (volatile guint *atomic,
                                                                guint           val);
 
-gpointer                g_atomic_pointer_get                  (volatile void  *atomic);
+GLIB_AVAILABLE_IN_ALL
+gpointer                g_atomic_pointer_get                  (const volatile void *atomic);
+GLIB_AVAILABLE_IN_ALL
 void                    g_atomic_pointer_set                  (volatile void  *atomic,
                                                                gpointer        newval);
+GLIB_AVAILABLE_IN_ALL
 gboolean                g_atomic_pointer_compare_and_exchange (volatile void  *atomic,
                                                                gpointer        oldval,
                                                                gpointer        newval);
+GLIB_AVAILABLE_IN_ALL
 gssize                  g_atomic_pointer_add                  (volatile void  *atomic,
                                                                gssize          val);
+GLIB_AVAILABLE_IN_2_30
 gsize                   g_atomic_pointer_and                  (volatile void  *atomic,
                                                                gsize           val);
+GLIB_AVAILABLE_IN_2_30
 gsize                   g_atomic_pointer_or                   (volatile void  *atomic,
                                                                gsize           val);
+GLIB_AVAILABLE_IN_ALL
 gsize                   g_atomic_pointer_xor                  (volatile void  *atomic,
                                                                gsize           val);
 
-#ifndef G_DISABLE_DEPRECATED
+GLIB_DEPRECATED_IN_2_30_FOR(g_atomic_int_add)
 gint                    g_atomic_int_exchange_and_add         (volatile gint  *atomic,
                                                                gint            val);
-#endif
 
 G_END_DECLS
 
-#if defined(__GNUC__) && defined(G_ATOMIC_OP_USE_GCC_BUILTINS)
+#if defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
+
+/* We prefer the new C11-style atomic extension of GCC if available */
+#if defined(__ATOMIC_SEQ_CST)
+
+#define g_atomic_int_get(atomic) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    gint gaig_temp;                                                          \
+    (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
+    __atomic_load ((gint *)(atomic), &gaig_temp, __ATOMIC_SEQ_CST);          \
+    (gint) gaig_temp;                                                        \
+  }))
+#define g_atomic_int_set(atomic, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    gint gais_temp = (gint) (newval);                                        \
+    (void) (0 ? *(atomic) ^ (newval) : 1);                                   \
+    __atomic_store ((gint *)(atomic), &gais_temp, __ATOMIC_SEQ_CST);         \
+  }))
+
+#if defined(glib_typeof)
+#define g_atomic_pointer_get(atomic)                                       \
+  (G_GNUC_EXTENSION ({                                                     \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));               \
+    glib_typeof (*(atomic)) gapg_temp_newval;                              \
+    glib_typeof ((atomic)) gapg_temp_atomic = (atomic);                    \
+    __atomic_load (gapg_temp_atomic, &gapg_temp_newval, __ATOMIC_SEQ_CST); \
+    gapg_temp_newval;                                                      \
+  }))
+#define g_atomic_pointer_set(atomic, newval)                                \
+  (G_GNUC_EXTENSION ({                                                      \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                \
+    glib_typeof ((atomic)) gaps_temp_atomic = (atomic);                     \
+    glib_typeof (*(atomic)) gaps_temp_newval = (newval);                    \
+    (void) (0 ? (gpointer) * (atomic) : NULL);                              \
+    __atomic_store (gaps_temp_atomic, &gaps_temp_newval, __ATOMIC_SEQ_CST); \
+  }))
+#else /* if !defined(glib_typeof) */
+#define g_atomic_pointer_get(atomic) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    gpointer gapg_temp_newval;                                               \
+    gpointer *gapg_temp_atomic = (gpointer *)(atomic);                       \
+    __atomic_load (gapg_temp_atomic, &gapg_temp_newval, __ATOMIC_SEQ_CST);   \
+    gapg_temp_newval;                                                        \
+  }))
+#define g_atomic_pointer_set(atomic, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    gpointer *gaps_temp_atomic = (gpointer *)(atomic);                       \
+    gpointer gaps_temp_newval = (gpointer)(newval);                          \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    __atomic_store (gaps_temp_atomic, &gaps_temp_newval, __ATOMIC_SEQ_CST);  \
+  }))
+#endif /* !defined(glib_typeof) */
+
+#define g_atomic_int_inc(atomic) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
+    (void) __atomic_fetch_add ((atomic), 1, __ATOMIC_SEQ_CST);               \
+  }))
+#define g_atomic_int_dec_and_test(atomic) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
+    __atomic_fetch_sub ((atomic), 1, __ATOMIC_SEQ_CST) == 1;                 \
+  }))
+#define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    gint gaicae_oldval = (oldval);                                           \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ (newval) ^ (oldval) : 1);                        \
+    __atomic_compare_exchange_n ((atomic), &gaicae_oldval, (newval), FALSE, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST) ? TRUE : FALSE; \
+  }))
+#define g_atomic_int_add(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
+    (gint) __atomic_fetch_add ((atomic), (val), __ATOMIC_SEQ_CST);           \
+  }))
+#define g_atomic_int_and(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
+    (guint) __atomic_fetch_and ((atomic), (val), __ATOMIC_SEQ_CST);          \
+  }))
+#define g_atomic_int_or(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
+    (guint) __atomic_fetch_or ((atomic), (val), __ATOMIC_SEQ_CST);           \
+  }))
+#define g_atomic_int_xor(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
+    (guint) __atomic_fetch_xor ((atomic), (val), __ATOMIC_SEQ_CST);          \
+  }))
+
+#if defined(glib_typeof)
+#define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof (oldval) == sizeof (gpointer));                  \
+    glib_typeof ((oldval)) gapcae_oldval = (oldval);                         \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    __atomic_compare_exchange_n ((atomic), &gapcae_oldval, (newval), FALSE, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST) ? TRUE : FALSE; \
+  }))
+#else /* if !defined(glib_typeof) */
+#define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof (oldval) == sizeof (gpointer));                  \
+    gpointer gapcae_oldval = (gpointer)(oldval);                             \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    __atomic_compare_exchange_n ((atomic), &gapcae_oldval, (newval), FALSE, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST) ? TRUE : FALSE; \
+  }))
+#endif /* defined(glib_typeof) */
+#define g_atomic_pointer_add(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
+    (gssize) __atomic_fetch_add ((atomic), (val), __ATOMIC_SEQ_CST);         \
+  }))
+#define g_atomic_pointer_and(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    gsize *gapa_atomic = (gsize *) (atomic);                                 \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gsize));                    \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
+    (gsize) __atomic_fetch_and (gapa_atomic, (val), __ATOMIC_SEQ_CST);       \
+  }))
+#define g_atomic_pointer_or(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    gsize *gapo_atomic = (gsize *) (atomic);                                 \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gsize));                    \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
+    (gsize) __atomic_fetch_or (gapo_atomic, (val), __ATOMIC_SEQ_CST);        \
+  }))
+#define g_atomic_pointer_xor(atomic, val) \
+  (G_GNUC_EXTENSION ({                                                       \
+    gsize *gapx_atomic = (gsize *) (atomic);                                 \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gsize));                    \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
+    (gsize) __atomic_fetch_xor (gapx_atomic, (val), __ATOMIC_SEQ_CST);       \
+  }))
+
+#else /* defined(__ATOMIC_SEQ_CST) */
 
+/* We want to achieve __ATOMIC_SEQ_CST semantics here. See
+ * https://en.cppreference.com/w/c/atomic/memory_order#Constants. For load
+ * operations, that means performing an *acquire*:
+ * > A load operation with this memory order performs the acquire operation on
+ * > the affected memory location: no reads or writes in the current thread can
+ * > be reordered before this load. All writes in other threads that release
+ * > the same atomic variable are visible in the current thread.
+ *
+ * “no reads or writes in the current thread can be reordered before this load”
+ * is implemented using a compiler barrier (a no-op `__asm__` section) to
+ * prevent instruction reordering. Writes in other threads are synchronised
+ * using `__sync_synchronize()`. It’s unclear from the GCC documentation whether
+ * `__sync_synchronize()` acts as a compiler barrier, hence our explicit use of
+ * one.
+ *
+ * For store operations, `__ATOMIC_SEQ_CST` means performing a *release*:
+ * > A store operation with this memory order performs the release operation:
+ * > no reads or writes in the current thread can be reordered after this store.
+ * > All writes in the current thread are visible in other threads that acquire
+ * > the same atomic variable (see Release-Acquire ordering below) and writes
+ * > that carry a dependency into the atomic variable become visible in other
+ * > threads that consume the same atomic (see Release-Consume ordering below).
+ *
+ * “no reads or writes in the current thread can be reordered after this store”
+ * is implemented using a compiler barrier to prevent instruction reordering.
+ * “All writes in the current thread are visible in other threads” is implemented
+ * using `__sync_synchronize()`; similarly for “writes that carry a dependency”.
+ */
 #define g_atomic_int_get(atomic) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
+    gint gaig_result;                                                        \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
+    (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
+    gaig_result = (gint) *(atomic);                                          \
     __sync_synchronize ();                                                   \
-    (gint) *(atomic);                                                        \
+    __asm__ __volatile__ ("" : : : "memory");                                \
+    gaig_result;                                                             \
   }))
 #define g_atomic_int_set(atomic, newval) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ (newval) : 0);                                   \
+    (void) (0 ? *(atomic) ^ (newval) : 1);                                   \
+    __sync_synchronize ();                                                   \
+    __asm__ __volatile__ ("" : : : "memory");                                \
     *(atomic) = (newval);                                                    \
+  }))
+#define g_atomic_pointer_get(atomic) \
+  (G_GNUC_EXTENSION ({                                                       \
+    gpointer gapg_result;                                                    \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    gapg_result = (gpointer) *(atomic);                                      \
+    __sync_synchronize ();                                                   \
+    __asm__ __volatile__ ("" : : : "memory");                                \
+    gapg_result;                                                             \
+  }))
+#if defined(glib_typeof)
+#define g_atomic_pointer_set(atomic, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
     __sync_synchronize ();                                                   \
+    __asm__ __volatile__ ("" : : : "memory");                                \
+    *(atomic) = (glib_typeof (*(atomic))) (gsize) (newval);                  \
   }))
+#else /* if !defined(glib_typeof) */
+#define g_atomic_pointer_set(atomic, newval) \
+  (G_GNUC_EXTENSION ({                                                       \
+    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    __sync_synchronize ();                                                   \
+    __asm__ __volatile__ ("" : : : "memory");                                \
+    *(atomic) = (gpointer) (gsize) (newval);                                         \
+  }))
+#endif /* defined(glib_typeof) */
+
 #define g_atomic_int_inc(atomic) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
+    (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
     (void) __sync_fetch_and_add ((atomic), 1);                               \
   }))
 #define g_atomic_int_dec_and_test(atomic) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ *(atomic) : 0);                                  \
+    (void) (0 ? *(atomic) ^ *(atomic) : 1);                                  \
     __sync_fetch_and_sub ((atomic), 1) == 1;                                 \
   }))
 #define g_atomic_int_compare_and_exchange(atomic, oldval, newval) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ (newval) ^ (oldval) : 0);                        \
-    (gboolean) __sync_bool_compare_and_swap ((atomic), (oldval), (newval));  \
+    (void) (0 ? *(atomic) ^ (newval) ^ (oldval) : 1);                        \
+    __sync_bool_compare_and_swap ((atomic), (oldval), (newval)) ? TRUE : FALSE; \
   }))
 #define g_atomic_int_add(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ (val) : 0);                                      \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
     (gint) __sync_fetch_and_add ((atomic), (val));                           \
   }))
 #define g_atomic_int_and(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ (val) : 0);                                      \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
     (guint) __sync_fetch_and_and ((atomic), (val));                          \
   }))
 #define g_atomic_int_or(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ (val) : 0);                                      \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
     (guint) __sync_fetch_and_or ((atomic), (val));                           \
   }))
 #define g_atomic_int_xor(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gint));                     \
-    (void) (0 ? *(atomic) ^ (val) : 0);                                      \
+    (void) (0 ? *(atomic) ^ (val) : 1);                                      \
     (guint) __sync_fetch_and_xor ((atomic), (val));                          \
   }))
 
-#define g_atomic_pointer_get(atomic) \
-  (G_GNUC_EXTENSION ({                                                          \
-    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    __sync_synchronize ();                                                   \
-    (gpointer) *(atomic);                                                    \
-  }))
-#define g_atomic_pointer_set(atomic, newval) \
-  (G_GNUC_EXTENSION ({                                                          \
-    G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    (void) (0 ? (gpointer) *(atomic) : 0);                                   \
-    *(atomic) = (__typeof__ (*(atomic))) (gsize) (newval);                   \
-    __sync_synchronize ();                                                   \
-  }))
 #define g_atomic_pointer_compare_and_exchange(atomic, oldval, newval) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    (void) (0 ? (gpointer) *(atomic) : 0);                                   \
-    (gboolean) __sync_bool_compare_and_swap ((atomic), (oldval), (newval));  \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    __sync_bool_compare_and_swap ((atomic), (oldval), (newval)) ? TRUE : FALSE; \
   }))
 #define g_atomic_pointer_add(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    (void) (0 ? (gpointer) *(atomic) : 0);                                   \
-    (void) (0 ? (val) ^ (val) : 0);                                          \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
     (gssize) __sync_fetch_and_add ((atomic), (val));                         \
   }))
 #define g_atomic_pointer_and(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    (void) (0 ? (gpointer) *(atomic) : 0);                                   \
-    (void) (0 ? (val) ^ (val) : 0);                                          \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
     (gsize) __sync_fetch_and_and ((atomic), (val));                          \
   }))
 #define g_atomic_pointer_or(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    (void) (0 ? (gpointer) *(atomic) : 0);                                   \
-    (void) (0 ? (val) ^ (val) : 0);                                          \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
     (gsize) __sync_fetch_and_or ((atomic), (val));                           \
   }))
 #define g_atomic_pointer_xor(atomic, val) \
-  (G_GNUC_EXTENSION ({                                                          \
+  (G_GNUC_EXTENSION ({                                                       \
     G_STATIC_ASSERT (sizeof *(atomic) == sizeof (gpointer));                 \
-    (void) (0 ? (gpointer) *(atomic) : 0);                                   \
-    (void) (0 ? (val) ^ (val) : 0);                                          \
+    (void) (0 ? (gpointer) *(atomic) : NULL);                                \
+    (void) (0 ? (val) ^ (val) : 1);                                          \
     (gsize) __sync_fetch_and_xor ((atomic), (val));                          \
   }))
 
-#else /* defined(__GNUC__) && defined(G_ATOMIC_OP_USE_GCC_BUILTINS) */
+#endif /* !defined(__ATOMIC_SEQ_CST) */
+
+#else /* defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) */
 
 #define g_atomic_int_get(atomic) \
   (g_atomic_int_get ((gint *) (atomic)))
@@ -187,11 +405,11 @@ G_END_DECLS
 #define g_atomic_int_add(atomic, val) \
   (g_atomic_int_add ((gint *) (atomic), (val)))
 #define g_atomic_int_and(atomic, val) \
-  (g_atomic_int_and ((gint *) (atomic), (val)))
+  (g_atomic_int_and ((guint *) (atomic), (val)))
 #define g_atomic_int_or(atomic, val) \
-  (g_atomic_int_or ((gint *) (atomic), (val)))
+  (g_atomic_int_or ((guint *) (atomic), (val)))
 #define g_atomic_int_xor(atomic, val) \
-  (g_atomic_int_xor ((gint *) (atomic), (val)))
+  (g_atomic_int_xor ((guint *) (atomic), (val)))
 #define g_atomic_int_inc(atomic) \
   (g_atomic_int_inc ((gint *) (atomic)))
 #define g_atomic_int_dec_and_test(atomic) \
@@ -212,6 +430,6 @@ G_END_DECLS
 #define g_atomic_pointer_xor(atomic, val) \
   (g_atomic_pointer_xor ((atomic), (gsize) (val)))
 
-#endif /* defined(__GNUC__) && defined(G_ATOMIC_OP_USE_GCC_BUILTINS) */
+#endif /* defined(G_ATOMIC_LOCK_FREE) && defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4) */
 
 #endif /* __G_ATOMIC_H__ */