* src/system.h: Include alloca.h.

* src/main.c (main) [C_ALLOCA]: Call alloca (0).

src/main.c

@@ -119,6 +119,12 @@ main (int argc, char *argv[])
 
   output_files ();
 
+  /* If using alloca.c, flush the alloca'ed memory for the benefit of
+     people running Bison as a library in IDEs.  */
+#if C_ALLOCA
+    alloca (0);
+#endif
+
   return complain_message_count ? EXIT_FAILURE : EXIT_SUCCESS;
 }