-AC_CHECK_HEADER(readline/readline.h, HaveReadlineReadlineH=YES, HaveReadlineReadlineH=NO)
-AC_CHECK_HEADER(readline/history.h, HaveReadlineHistoryH=YES, HaveReadlineHistoryH=NO)
+AC_CHECK_HEADER(readline/readline.h, [HaveReadlineReadlineH=YES], [HaveReadlineReadlineH=NO])
+AC_CHECK_HEADER(readline/history.h, [HaveReadlineHistoryH=YES], [HaveReadlineHistoryH=NO])