+/* On Cygwin there are two heaps. temacs uses the static heap
+ (defined in sheap.c and managed with bss_sbrk), and the dumped
+ emacs uses the Cygwin heap (managed with sbrk). When emacs starts
+ on Cygwin, it reinitializes malloc, and we save the old info for
+ use by free and realloc if they're called with a pointer into the
+ static heap.
+
+ Currently (2011-08-16) the Cygwin build doesn't use ralloc.c; if
+ this is changed in the future, we'll have to similarly deal with
+ reinitializing ralloc. */
+#ifdef CYGWIN
+extern void *bss_sbrk (ptrdiff_t size);