Merge branch 'boehm-demers-weiser-gc' into bdw-gc-static-alloc

[bpt/guile.git] / libguile / boehm-gc.h

diff --git a/libguile/boehm-gc.h b/libguile/boehm-gc.h
index b3a8514..9a92d08 100644 (file)
--- a/libguile/boehm-gc.h
+++ b/libguile/boehm-gc.h
@@ -45,4 +45,20 @@
 typedef void *GC_PTR;
 #endif
 
+
+/* Return true if PTR points to the heap.  */
+#define SCM_I_IS_POINTER_TO_THE_HEAP(ptr)      \
+  (GC_base (ptr) != NULL)
+
+/* Register a disappearing link for the object pointed to by OBJ such that
+   the pointer pointed to be LINK is cleared when OBJ is reclaimed.  Do so
+   only if OBJ actually points to the heap.  See
+   http://thread.gmane.org/gmane.comp.programming.garbage-collection.boehmgc/2563
+   for details.  */
+#define SCM_I_REGISTER_DISAPPEARING_LINK(link, obj)            \
+  ((SCM_I_IS_POINTER_TO_THE_HEAP (obj))                                \
+   ? GC_GENERAL_REGISTER_DISAPPEARING_LINK ((link), (obj))     \
+   : 0)
+
+
 #endif /* SCM_BOEHM_GC_H */