Replaced #if HAVE_X with #ifdef HAVE_X as the former test is troublemaker with #define HAVE_X where #define HAVE_X 1|0 is meant.
diff --git a/arraylist.c b/arraylist.c
index 9a673d6..2d44a18 100644
--- a/arraylist.c
+++ b/arraylist.c
@@ -11,12 +11,12 @@
#include "config.h"
-#if STDC_HEADERS
+#ifdef STDC_HEADERS
# include <stdlib.h>
# include <string.h>
#endif /* STDC_HEADERS */
-#if defined HAVE_STRINGS_H && !defined _STRING_H && !defined __USE_BSD
+#if defined(HAVE_STRINGS_H) && !defined(_STRING_H) && !defined(__USE_BSD)
# include <strings.h>
#endif /* HAVE_STRINGS_H */